Actual questions with answers presented to Master Gardeners at clinics in our community covering a wide range of gardening topics. Some are quite unique while others more frequently posed. The following responses have been researched by members of the Victoria Master Gardener Association (VMGA). Check back on a regular basis to find new questions presented each month. You can search this file using Control F on a PC or Command F on an Apple.
For direct answers to your gardening questions please e-mail your question to the Victoria Master Gardeners at info@msvmga.org.
June 2022
- What are great plants for under shade?
Before planting your shade garden, there are a few things that you’ll need think about and to ask yourself: How much sun does the area get? Does the area get and/or hold water or is it very dry? Will I be watering and mulching? What size or types of plants do I want – groundcovers to trees, annuals or perennials? Do I want flowers or mostly foliage? Are there other conditions or interests, such as plants for pollinators?
Here are a couple of ideas that touch on each of these questions. There are also many resources to research and I’ve listed a few of them below.
How much sun do I get? There are basically four classes to determine the amount of sun you get. Once you are familiar with the level of sun, you can select the type of plant and variety that will work in your area. The four general classes are: Light shade or partial shade receives 4-6 hours of sun, mostly in the morning; Dappled or filtered shade is sunlight filtering through a canopy of trees; Full shade refers to areas with 2 or less hours of sun a day; Deep shade is an area that receives no direct sunlight.
General ideas for plants that will thrive in shady areas – please check the variety to be sure it’s right for you.
Annuals: English daisy (Bellis perennis), Lobelia (Lobelia erinus), Scarlet sage (Salvia splendens), Pansy (Viola tricolour var. hotensis), Begonia (Begonia spp.), Coleus (Coleus blumeii).
Grasses: Sedges (Carex spp.), Japanese forest grass (Hakonechloa), Black mondo grass (Ophiopogon japonica; O. planiscapus ‘Nigrescens’), Oriental fountain grass (Pennisetum), Reed grass (Stipa brachytricha)
Groundcovers: Lady’s mantle (Alchemilla mollis), Bunchberry (Cornus canadensis), Baby’s tears (Soleirolia soleirolii), Sweet woodruff (Galium odoratum), Japanese spurge (Pachysandra terminalis)
Perennials: Siberian bugloss (Brunnera macrophylla), Hardy cyclamen (Cyclamen spp.), Cranesbill (Geranium macrorrhizum), Lungwort (Pulmonaria spp.), Bishop’s hat (Epimedium spp.), Hellebore (Helleborus spp.), Coral bells (Heuchera spp.), Plantain lily (Hosta spp.),
Ferns (e.g., Polystichum: P. munitum — sword fern; P. setiferum — soft shield/Alaskan ferns; P. acrostichoides — Christmas fern; P. tsus-simense — Korean Rock Fern)
Shrubs: Variegated aucuba (Aucuba japonica), Skimmia, Camellias (Camellia japonica or Camellia sasanqua), Fuchsia (Fuchsia hybrida), Lily of the valley shrub (Pieris japonica), Evergreen euonymus (e.g., Euonymus fortunei), Barberry (Berberis thunbergia ‘Aurea’, Winter daphne (Daphne odora), Oregon grape (Mahonia aquifolium), Euonymus japonica, Japanese holly (Ilex crenata)
Trees: Dogwood (Cornus kousa or Cornus nuttalii), Vine maple (Acer circinatum), Japanese snowbell (Styrax japonica), Western yew (Taxus brevifolia)
Vines: Clematis (Clematis chrysocoma), Honeysuckle (Lonicera spp.), Virginia creeper (Parthenocissus quinquefolia)
Drought tolerant: Bears breeches (Acanthus mollis), Anemone (Anemone x lipsiensis) Camellia, Helleborus, Western columbine (Aquilegia Formosa)
Sources
The Informed Gardener. Linda Chalker-Scott.
Fine Gardening
McNeilan, R. &J. (1997) The Pacific Northwest Gardener’s Book of Lists.
The Old Farmer’s Almanac
Washington State University. Planting in Dry Shade in the Pacific Northwest
Xera Plants Inc. Dry shade
- Are there any food producing shrubs that thrive in Victoria climate?
We are all seeking ways to enhance our gardens, and particularly enhancing our edible landscapes. Consider selecting shrubs, small/dwarf fruit trees or perennials that give you a bounty of tasty treats. Generally, you’ll need to have a spot with good sun (8 hours a day) as well as good soil with good drainage.
Shrubs:
Blueberries (Vaccinium corymbosum cultivars) - zone 3 Blueberries form a rounded, upright shrub about 4-5 feet tall at maturity. The simple blue-green leaves turn brilliant crimson in autumn and with an intricate branching structure, blueberries add winter interest. You’ll need at least two different cultivars to ensure cross-pollination;
Red Currants (Ribes rubrum cultivars) and Black Currants (R. nigrum cultivars) - zone 4 Currants form shrubs live 12-`5 years and grow up to about 5 feet high. An excellent fruit for pies, wine and jelly, red and black currants ripen from June to August on high-yielding shrubs. Their early-spring blooms of brilliant pink or white attract hummingbirds;
Gooseberries (Ribes grossularia cultivars) - zone 5 This is an easy to grow shrub, productive for up to 15 years, with fruit that ripens in early July. The plant has a 4 ft round shape with green-white flowers that attract hummingbirds. Can be grown in full sun or semi-shade;
Raspberries (Rubus idaeus cultivars) - zone 4 Individual raspberry canes can live up to 10 years, each year growing new canes that produce the fruit in their second year. Most raspberry varieties are self pollinating. They need sun and well-drained good soil and will require annual pruning;
Blackberries (Rubus fruticosus cultivars) - zone 4 Blackberries can be erect (bushes) or trailing (long canes requiring support), with thorns or thornless. They are easy to grow and require sun, plenty of moisture, good soil with good drainage. They produce beautiful sweet berries on second year canes, so pruning is important. Consider mulching to protect and retain moisture;
Kiwi – (Actinidia Argutua) – fast growing deciduous vines , similar to grape vines, that prefer warmer temperatures. A good choice for this area is to select hardy Kiwi such as the self-fertile Issai which has fruit more similar to a grape than the traditional fuzzy kiwi. They have smooth edible skins, excellent flavour and aroma.
Trees
Cornelian cherry dogwood (Cornus mas) - zone 4 Large multi-stemmed shrub that is sometimes trained as a small tree. This hard-working tree is truly a four-season delight, with masses of yellow spring blooms, abundant red fruit, fall colour and beautiful bark for winter interest;
Fig tree (Ficus carica) - zone 7 This deciduous tree has attractive foliage with small green fruits that darken when ripe. Fig trees can grow tall but respond well to pruning, to keep them quite small. Fig trees are good grown in pots because the roots do best in a tight space and the pots can also be brought inside in colder months;
Stone fruits like peaches, plums These deciduous trees can be espaliered keeping them trim and easily managed; Apple, pear tree or stone fruits – dwarf varieties – Zones 3-6 – Dwarf apple or pear trees are among the most sought after small trees. They need a lot of sun and at least two varieties for successful pollination. Dwarf apple trees will start bearing fruit 2-3 years after planting; pears will be 3 to 10 years to produce fruit and stone fruits like peaches will be 2-5 years. Be sure to check size at maturity as well as hardiness for your garden zone.
Perennials: Asparagus (Asparagus officinalis) - zone 2 This makes a beautiful "hedge," with ferny foliage up to 1 m (3 ft) high. Wait until plants are three years old to begin harvesting the spears; Jerusalem artichoke (Helianthus tuberosus) - zone 4 A member of the sunflower family, this very vigorous perennial can reach 10 ft high and has a gorgeous yellow sunflower-type bloom; Rhubarb (Rheum) - zone 5 A classic reliable perennial, rhubarb has been grown for many years in gardens as a staple. Rhubarb is easy to grow, productive and attractive with its bold, tropical-looking leaves and ruby-red, green or pink stems.
Sources
Almanac - Blackberries
Oregon State University - Berries
The Spruce – Dwarf Trees You Can Grow in Small Yards and Cornelian Cherry Dogwood
University of Minnesota Extension – Growing Apples, Pears or Stone fruits in the Home Garden
Washington State University – Growing Kiwifruit
May 2022
- How do I prune lace cap hydrangeas and will they come back after hard prune?
How you prune your lace-cap hydrangea depends on what you would like to achieve and the state of your plant. It is important to remember that lace-caps bloom on the previous year’s growth, so keep this in mind when pruning your plant.
If you want to extend the flowering period of your lacecap hydrangea, you can dead-head the flowers by cutting back to the second set of leaves below the flowerhead right after flowering. This will have the advantage of preventing the plant from spending energy to set seed instead of directing that energy into growth.
In late winter/early spring, cut out any dead, diseased, or damaged stems to the base of the plant. Also, cut two or three of the oldest flowering stems back to the base of the plant at this time. The plant will send up new shoots that will bloom next year. If your hydrangea is well-established, but requires more extensive pruning, you can prune out up to 1/3 of the oldest flowering stems at this time.
If your hydrangea is well-established but in need of a complete renovation you can cut it down to the ground in late winter/early spring. However, keep in mind you will not get blooms until the second year.
Sources
https://www.hydrangeaguide.com/pruning-lacecap-hydrangeas/
https://www.rhs.org.uk/plants/hydrangea/pruning-guide
Victoria Master Gardenenr Association Training Course notes by Jane Tice
- My Rhubarb plants that are 4-5 years old have developed a single large growth in the centre that is much taller than the foliage. What is this and what do I do about it?
Rhubarb is an easy to grow, long lasting vegetable, largely free of pests and diseases. The single large growth you see in the centre of the plant is the flower stalk and usually develops in a plant that is mature, such as the ones you are growing. Towering flower stalks are sent up in early summer with tight clusters of buds that open to pink flowers. You will want to cut off the flower stalk as soon as it appears so the rhubarb can focus plant energy on developing the edible stalks. If you do not cut off the flower stalk, the plant will focus all its energy on producing flowers and seeds, and your edible harvest will be reduced.
To reduce the risk of root rot, cut the flower stalk as low as possible to the ground so that the cut surface will not be so exposed to seasonal rain or standing water. Also, remove any leaves and edible stalks that are limp and yellowing which can attract slugs and snails. Only the stalks of rhubarb are edible so the leaves should be composted as they contain oxalic acid which can be poisonous. Interestingly, the deer in my garden do eat the rhubarb leaves and do not seem to have suffered at all.
Sources
https://www.rhs.org.uk/vegetables/rhubarb/grow-your-own
What’s Wrong With My Vegetable Garden – Organic Solutions for All Your Vegetables, David Deardorff & Kathryn Wadsworth, 2011, page 96 “Rhubarb”
- I have a Peace rose which I got last year. In the summer months, I saw a lot of white flies on the plant. I sprayed the rose with a mixture of soap, water, and baking soda. I don’t know if it helped much. I noticed this March I have brown spots on the stems all the way down to the ground (cane canker?). There are new leaves coming out on the canes. What would you do to save this rose bush?
If you grow roses, you are almost guaranteed to encounter plant diseases. Although the Peace rose is meant to be a ‘disease resistant’ variety, it still requires lots of attention to detail in terms of plant health and care. I would suggest that the whitefly infestation last summer has generally weakened the plant and allowed the stem canker to develop more easily. As whitefly feed on plant sap, they cause leaf damage, transmit harmful plant viruses, and cause a host of other problems. They are hard to get rid of as they locate under the leaves and are so small, they are difficult to spot.
Stem canker and dieback is a disease of stress and reveals itself by turning the canes black most notably in locations where the plant was pruned last and is a potentially fatal fungal infection in your rose. These fungi enter healthy canes through wounds caused by winter injury, improper pruning, wind, hail damage, or flower cutting. Cankers can enlarge until they surround the cane and/or reach the base (crown) of the plant spreading to other canes or killing the plant.
There are several fungi that cause cankers on roses. The different fungi can cause different-looking cankers, but they usually produce brown, oval-shaped, sunken or shriveled areas anywhere on the cane. The cane dies and leaves wilt from that point onward. Cankers should be pruned out each year: use disinfected secateurs, make the cut well below the affected tissue; protect the plant from cold or freeze injury by providing adequate mulch cover over the winter; add adequate amounts of fertilizer in the spring. There are no fungicides specifically available to control stem canker but keep plants healthy by controlling black spot, powdery mildew, and insects.
As wounds are a major way the canker fungus enters the plant, prune properly on an outward facing bud. This will help avoid too many branches growing into the center of the plant that may cross and rub together. Make all pruning cuts well below the diseased areas, and prune about one-fourth inch above an outward-facing bud node, without cutting the nodal tissue, at a 45-degree angle. Prune live canes in the spring, not fall. Disinfect cutting tools after use on a diseased plant. As it sounds like your Peace Rose is seriously infected I would prune farther than that, possibly removing 75% of a blackened stem. Follow up with a fungicidal treatment to give your roses an added boost against reinfection.
Continue to keep an eye on the whitefly. Look for insects or eggs on the backside of leaves. Watch for swarms of tiny bugs that fly off plants when you approach. Check for the presence of black sooty mold or ants, which are attracted to the sweet honeydew substance that whiteflies secrete. The first line of defense is to gently spray the rose with water to dislodge whitefly eggs and nymphs. Because nymphs don’t move after the initial creeping phase, they will starve and die when removed from their food source. Keep leaves clean to control honeydew and mold, wipe down affected leaves with a damp cloth or spray with water. Try horticultural oils such as neem oil that will kill whiteflies at all life stages and discourage black sooty mold.
As canker can affect nearby plants, I would keep a close eye on surrounding plants. Give your Peace rose the suggested treatments and if you see no improvement, or if the situation worsens, remove the rose entirely and dispose of it, do not compost. Also, do not plant anything else in that spot for a year or two to allow the soil to cleanse.
References
Natural Insect, Weed & Disease Control, Linda A. Gilkeson, 2013, page 52 “Whiteflies”.
www.missouribotanicalgarden.org
https://www.gardendesign.com/how-to/whitefly
April 2022
- I want to try 'in-ground' composting. Is this a good idea and why?
Trench or hole composting is used for a number of reasons. Soil structure and composition are improved and enriched with a marked increase in earth worms and other beneficial soil organisms over time. This improves the vigour and overall health of plants. In addition, it is a good method to use if you don’t have room for a composter or don’t have a sunny location to place a compost bin or pile. It is invisible, doesn’t produce odours and takes very little effort. You don’t have to turn and layer it as you would an above ground compost pile. It does not attract critters such as squirrels, rats and mice, racoons and the neighbourhood cats and dogs, as they are not able to access the compost. Compost holes only require four easy steps (in fact only three if you substitute store-bought compost instead of kitchen scraps). The materials required are minimal: a shovel or spade, kitchen scraps and other compostable materials or store-bought compost. No activators are needed to speed up decomposition. The holes or trenches are a simple method for building the soil in any garden. In addition, in raised beds, the soil is typically soft, so the holes are easy to dig.
The ‘How’ to do it and things to consider:
Dig a trench or hole, put in the kitchen and/or yard waste, and fill the trench or hole in. You can enrich your soil weekly—even daily if your kitchen produces enough compostable waste.
Over time the waste is turned into decomposed, organic matter or humus containing millions of microorganisms and there is nothing better for your plants. Once you’ve collected one to two quarts of kitchen waste, chop up any large pieces with shears or your spade but don’t run it through a blender or compact it. The vegetable and fruit scraps you’ve collected will be broken down by bacteria that works aerobically. In other words, the bacteria require oxygen in order to decompose.
Dig a hole wherever you’d like to improve your soil. It could be in your flowerbeds, vegetable garden, raised beds or somewhere you’ll sow seeds or plant seedlings. It could even be the site where you plan to plant a tree.
Trench composting works well in larger vegetable gardens and involves digging a trench approximately 12 to 18 inches deep, filling it with roughly 4 to 6 inches of yard waste and/or kitchen scraps and then back filling with the soil you removed.
Trenches can be used either in a rotation cycle, where you would divide the garden into zones; an actively growing zone, a path and a trench composting zone. Each year you would rotate the zones, allowing you to compost the whole vegetable garden in 3 years.
The second method is to dig trenches in between the vegetable rows. This works well if you grow your vegetables in evenly spaced rows. Over time as everything breaks down and the compost will nourish nearby plants.
In the fall after harvesting the vegetables, use this technique in the areas where you have grown heavy feeders, like corn or squash. The following spring most of the material will have decomposed and you will be ready to plant again.
For smaller gardens, the trench composting system may not work well due to lack of space. Instead, you can use hole composting, which works in vegetable, flower, and perennial beds, near shrubs and just about anywhere where you can dig an 8” to 18” deep hole without too much root disturbance of nearby plants.
During both the dormant and active growing seasons, dig holes in the garden beds (annual and perennial) and bury kitchen and yard waste. In just a couple of years of composting using this method, there should be a noticeable difference in the health of the soil, and in the number of earth worms.
If you have a lot of kitchen waste and room for more than one hole, try the two-hole compost method.
First, dig a hole between the rows in your vegetable garden or in your flower bed. Dump one to two quarts of compostable materials into the hole and then fill it with dirt acquired from digging a second hole. Fill the second hole with more kitchen scraps and top it off with dirt, either from the first hole or from a third one.
If you are planning a new tree or shrub create a compost hole for it either in spring or summer.
Simply dig a hole about a foot deep in the spot where you intend to plant the tree. After adding kitchen waste and covering the waste with soil, top the hole with mulch. Mark the compost hole with a stick, flag, stake or some other identifying mark.
By spring planting time, the soil in the hole will be friable and rich, perfect for providing nourishment to the newest member of your landscape.
Materials to include for trench or hole composting: Try to aim for a mix of vegetable scraps and plant waste mixed with ‘brown’ items such as paper, cardboard, hay, straw, dead leaves and so on, for each hole or trench. For a long trench or multiple holes, you can mix everything in a big wheelbarrow, container or even on a tarp before emptying it into the dug areas.
Any or all of the following can be composted: dead leaves; kitchen scraps (fruit and vegetable scraps, including vegetable peelings like potato, turnip, parsnip, onion, carrot and yam peels; fruit peelings, such as apple, peach, pear & banana peels; vegetable& fruit cores, such as cabbage, lettuce, pear & apple cores; trimmings from mushrooms, lettuce, potatoes, celery and carrots; and nutshells); tea leaves and coffee grounds together with tea bags and coffee filters (provide nitrogen); crushed eggshells (add calcium and improve drainage); paper, including brown paper bags; fresh garden waste from trimming and weeding (avoid weed seed heads); wood chips; corrugated cardboard; fresh grass clippings; sawdust; manure; corn stalks and husks; hay; dry straw.
You can also collect items of household waste beyond kitchen scraps. For instance, black & white newspapers (shredded), cardboard egg cartons (torn into small pieces), wood ash and vacuum dirt are good ‘brown’ additions to your compost hole. You can even empty your hairbrush and your pet's hairbrush into your compost bucket. Hair contains nitrogen, which plants love.
Do not include meat, bones, grease and dairy products. Not only do they attract animals, but they take a long time to decompose.
Don't include any materials that might harbour disease, such as pet faeces and diseased houseplants. Also avoid adding items that contain ingredients that are potentially toxic to plants, such as coal ash and color newspaper supplements.
Sources:
https://peterboroughmastergardeners.com/2018/05/28/trench-or-hole-composting
http://www.dirtygardening.com/in-ground-composting.html
https://compost.bc.ca/wp-content/uploads/2015/06/5-Trenching.pdf (a non-profit organization with charitable status providing composting and ecological gardening education to CRD residents)
https://www.farmersalmanac.com/what-trench-composting-123957
- I am a new gardener and would like to grow vegetables. I have heard the soil pH is important. What is pH and how important is it for growing vegetables?
The pH describes the relative acidity or alkalinity of soil, which affects a plant’s ability to take up the nutrients needed to grow and thrive. It also influences the number of micro-organisms in the soil such as soil fungi and bacteria. These micro-organisms make dissolved nutrients from the soil available to feed plant roots. Rich, moist soils with a slightly acidic pH host more of these life forms compared to soils that are very acidic (peat bogs) or alkaline (limestone outcroppings or deserts).
pH is expressed as a number between 0 and 14. Soil with a pH of 7 is neutral, an acid soil has a lower value, and an alkaline soil has a higher one. Most plants grow best in soil that’s within a specific pH range, so it’s useful to know your soil’s pH.
Testing kits are easy to use and widely available in garden centres and online and there are also laboratories that will do testing for you.
Soil testing on Vancouver Island can be carried out at: https:// www.mblabs.com
The pH value of a soil is influenced by the kinds of parent materials from which the soil was formed. Soils developed from basic rocks generally have higher pH values than those formed from acid rocks.
Rainfall also affects soil pH. Water passing through the soil leaches basic nutrients such as calcium and magnesium from the soil. They are replaced by acidic elements such as aluminum and iron. For this reason, soils formed under high rainfall conditions such as the Pacific Northwest, are more acidic than those formed under arid (dry) conditions.
Having the right soil pH is key to growing a healthy garden, but it’s a factor that’s often not considered before adding amendments to improve nutrient levels or soil consistency. While these are also crucial things to consider, the pH of the soil plays a major role in how well your plants can absorb the nutrients you provide. The major impact that extremes in pH have on plant growth is related to either the availability of plant nutrients or the soil concentration of plant-toxic minerals. In highly acid soils, aluminum and manganese can become more available and more toxic to the plant. Also at low pH values, calcium, phosphorus and magnesium are less available to the plant. At pH values of 6.5 and above, phosphorus and most of the micronutrients become less available.
Most vegetables grow in slightly acidic to neutral soils. The following chart shows the ideal range for various types of produce. You can see that potatoes prefer the soil a little more acidic while Asparagus will grow in soil that is a little more alkaline. A range of between 5.5 and 7.5 is the sweet spot for most vegetables.
Preferred range for vegetables
6.0-8.0
6.0-7.5
6.0-7.5
6.0-7.0
6.0-7.5
6.0-7.0
5.5-7.0
5.5-7.5
5.8-7.0
6.0-7.0
5.5-7.0
5.5-8.0
6.0-7.5
6.0-7.0
6.0-7.5
5.5-7.0
4.8-6.5
5.5-7.5
6.0-7.0
6.0-7.5
6.0-7.5
5.5-7.0
5.5-7.5
Mulching vegetable beds with a layer of natural fertilizer such as compost and composted manure will increase the micro-organisms within the soil and help keep most soils within the correct pH range to keep a vegetable garden healthy. The decomposition of organic matter adds to soil acidity.
Elemental Sulphur, iron sulphate and other acidifying agents can sometimes be added to reduce pH in soil that is overly alkaline. Clay soils may require large amounts of acidifying material.
Sources:
https://hgic.clemson.edu/factsheet/changing-the-ph-of-your-soil
https://www.growveg.com/guides/soil-ph-for-organic-gardeners
https://www.almanac.com/plant-ph
Sustainable Gardening, T
- I currently have a climbing Lonicera in this South and West exposure adjacent to a wall. It is not doing great here. What might be a different option for this location?
Lonicera, Zones 4-10, is a beautiful, deciduous vine which grows well in the Pacific northwest. Before you decide to replace your vine, you may want to consider some of the ways you can ensure your vine thrives in its current location.
Possible reasons why your plant is not doing well include:
1. Location: The southwest exposure and planting against a wall may be contributing to drought conditions. While the vine itself prefers a sunny location, the roots of the vine must be protected from drying out, and kept consistently moist. This can be done by applying organic mulch to the base of the plant, underplanting the vine with a low growing groundcover to cover the roots and help to retain moisture, or ensuring consistent and even watering.
The idea is to mimic the natural habitat of the forest floor where the vine would be covered with leaf litter and other rich organic matter and the roots would be shaded by other plants and trees growing in the forest.
2. Soil Composition: Lonicera prefer soil rich in nutrients and once again, the location of the plant may be contributing to a depletion of soil nutrients. Applying good quality organic matter each year should help to replenish the soil as well as ensure adequate moisture retention and proper drainage.
3. Lonicera can be prone to powdery mildew. If your vine is showing signs of this problem, prune out the infected parts of the vine making sure to clean your pruners well afterward. Rake up and dispose of the infected leaves, keeping the area clean and tidy. Make sure to dispose of the infected leaves in the garbage and not in your compost bin. Ensuring your vine has proper nutrients and doesn’t dry out will help combat powdery mildew in the future.
If all else fails and you decide to replace your Lonicera with something else, there are vines that would do well in your location. Keep in mind that most vines require similar soil conditions and root protection, and some vines can damage the structure of your home (such as wisteria) and should be avoided for this location. The Star Jasmine may be a good alternative to the Lonicera. Trachelospermum jasminoides (Common name, Star Jasmine)ly is not only a visually stunning vine, but it also has a lovely fragrance. Zone 8-10, has glossy, dark green leaves, beautiful, delicate, fragrant white flowers. It usually blooms twice a year, and is drought tolerant once it is established. It can be susceptible to severe cold conditions but the protected southwest location, up against a wall should provide adequate protection.
Sources:
http://linnet.geog.ubc.ca/Atlas/Atlas.aspx?sciname=Lonicera hispidula
https://www.rhs.org.uk/plants/honeysuckle/climbing
http://www.pnwplants.wsu.edu/PlantDisplay.aspx?PlantID=197
https://www.greatplantpicks.org/search/plant-details/1851
https://www.rhs.org.uk/Search?query=star jasmine
https://www.gardenia.net/plant/trachelospermum-jasminoides-star-jasmine
- We’d like to get a cherry tree but don’t want one that is too tall. Any suggestions?
There are so many smaller varieties of cherry trees that could work for you. The following is a small sampling. The links, that are included in the sources section, are a great reference for further research as there are many more varieties that could work for you.
Prunus avium ‘Stella’ – Sweet Cherry – An RHS Award of Merit winner, dwarf variety grows 8-12 feet high, semi-dwarf 10-18 feet high, self-fertile, pretty, scented white clusters blooming early-mid spring, followed by dark red, sweet cherries in mid-summer. Requires netting when fruit is ripe. 600 chill hours required.
Prunus cerasus’Meteor’ – Tart Cherry – Cold hardy, zone 4-8, 10-14 feet high with a width of 8-12 feet. Large, bright red, tart cherries great for pies mid-late summer, disease resistant. Self-fertile. 800 chilling hours required (hours below 7c).
Prunus ‘Shogetsu’ - Blushing Bride Flowering Cherry is a Royal Horticultural Society, Award of Merit winner. This tree grows 15-20 feet high x 15 x 25 feet wide. It produces white, double, large hanging clusters in late spring. Red/orange leaves in the fall provide visual fall interest and makes a spectacular specimen tree. Fine for preserves.
Prunus serrulate ‘Shirotae’ – Mt. Fuji Flowering Cherry, is another RHS Award of Garden merit winner. With a 15-20 height and 15-25 width, it has a ‘spreading flat crown with arching branches’ and fits well into a smaller garden. Fall interest with bronze coloured leaves.
Prunus ‘snow fountains’ – Weeping Cherry, Zones 6-8, requiring full sun is a smaller option, growing 6 to 12 feet in height with a spread of 6-8 feet. Showy, white flowers producing small, black ornamental fruit-inedible. A beautiful, showy tree suitable for a garden bed or border location.
Like all fruit trees, cherry trees generally require full sun, moist, well-drained, and nutrient rich soil. Some varieties are self-fertile, such as ‘stella’ which means it doesn’t require a pollinating tree nearby. Some varieties such as Meteor require a certain number of cold hours below 7c in the winter to promote blooming in spring.
Sources:
http://www.pnwplants.wsu.edu/PlantDisplay.aspx?PlantID=499
http://www.pnwplants.wsu.edu/PlantDisplay.aspx?PlantID=846
http://www.pnwplants.wsu.edu/PlantDisplay.aspx?PlantID=701
http://www.pnwplants.wsu.edu/PlantDisplay.aspx?PlantID=226
http://www.pnwplants.wsu.edu/PlantDisplay.aspx?PlantID=786
https://www.gardenia.net/plant/prunus-shogetsu-japanese-flowering-cherry
https://www.gardenia.net/plant/prunus-snow-fountains
https://landscapeplants.oregonstate.edu/plants/prunus-serrulata-mt-fuji
https://landscapeplants.oregonstate.edu/plants/prunus-serrulata-shogetsu
https://www.gardenia.net/plant/prunus-avium-stella
https://www.gardenia.net/plant/prunus-cerasus-meteor
March 2022
- What can you tell me about Buddleja davidii? I would like one but heard they can be invasive and spread into surrounding natural areas.
Yes, you are correct that they can be invasive. The Invasive Species Council of BC advises that Butterfly bush is a perennial semi-evergreen multi-stemmed shrub that grows to 5 m tall with 25 cm long, green-silver leaves and very showy long, pointed, spike-shaped light purple to dark purple bunches of tiny flowers. If you look closely, the center of each tiny flower is typically bright orange. Butterflies often are attracted to its flowers.
This attractive, fast growing plant is considered problematic because of its ability to naturalize outside of gardens and rapidly invade and dominate disturbed natural areas across a wide range of physical conditions including disturbed, open areas and along coastal forest edges, roadsides, and especially on sunny stream edges and riverbanks where it replaces native plants. The butterfly bush produces lots of seeds and a single flower bunch can produce over 40,000 seeds. Seeds are spread by wind and water, and can still grow after being in the soil for many years.
If you want to add this to your garden, it is critical to select seedless, sterile and non-invasive varieties for your garden that have been approved for sale in your area. In some cases, they may be sold under the name “summer lilac” instead of “butterfly bush” to clarify that they have been approved by their respective departments of agriculture. Oregon State has published a list of approved cultivars. However, there is still a possibility that the sterile varieties (which are only about 98% sterile) can cross pollinate with an invasive non-sterile variety growing nearby. You can minimize this spread by removing spent flower clusters prior to formation/disbursement of seed.
There are also native plants that might be used as alternatives to Buddleja davidii, such as Spiraea douglasii (Hardhack) with a similar dense cluster of numerous small flowers; Lewis’s Mock Orange (Philadelphus lewisii); or California Lilac (Ceanothus spp. and hybrids). The Invasive Species Council of BC offers a number of other alternatives to butterfly bush in their pamphlet Grow Me Instead.
Sources:
American Horticultural Society. (2004). A-Z Encyclopedia of Garden Plants (pp. 194-196)
BC Invasive Species Council (n.d.). Grow Me Instead.
Oregon Department of Agriculture. (2020). Approved Sterile Buddleja Cultivars
Tallent-Halsell, N.G. & Watt, M.S., (2009). The Invasive Buddleja davidii (Butterfly Bush). In The New York Botanical Garden.
- We have some plum trees that were cut right down to the ground are now producing suckers. Will these suckers become viable plum trees?
Suckers are adventitious roots that form from roots of many fruit trees in response to stress conditions, such as flooding, nutrient deprivation, and wounding.They can even appear many feet away from the original tree and can become a nuisance. Plums are known to produce suckers, especially if the roots have been damaged or under stress, so it seems your cut-down plum tree may still have a root system.
Most plum trees are grafted onto a rootstock. The suckers are shoots growing from below the graft union on the tree. This means that shoots from below the graft union are growing from the rootstock. Rootstocks often are selected for characteristics like size (dwarf) and disease resistance – not fruit production or quality. Therefore these suckers would not become plum trees like the one you cut down, but would instead grow into the rootstock, which might be a viable plum but maybe not.As you’ve cut down the tree, you may need to remove as much of the root system as possible which should take care of the suckers. If that’s not possible, remove the suckers where they originate from on the root system, as close to the point of origin as possible. You may need to dig down a bit into the soil to find the base of the sucker. Any piece left can begin to regrow so this process may need to be repeated if suckers emerge again, but it is a simple task.
Sources:
Extension, Utah State University (2020). Managing suckers around fruit trees.
University Extension (2018). Knowleddgebase #461392. How to get rid of plum tree suckers.
Royal Horticultural Society (n.d.) Removing suckers and seedlings.
- Should the middle number of a fertilizer be higher?
The short answer is “it depends”! The three numbers on mixed fertilizer labels is called the analysis and is always these three nutrients in the same order: N-P-K. N stands for nitrogen, P for phosphorus, and K for potassium. The lower the numbers overall, the more likely the fertilizer is organic. For example, if you see 2-4-3 on the label, this means there is 2% available nitrogen, 4% available phosphorus and 3% available potassium.
Phosphorus, the middle number, is most useful and needed in newly seeded beds or for transplanted plants to boost root growth, and it aids in flower and fruit production as well. An excellent organic source of this nutrient is bone meal. Though soils generally contain lots of phosphorus, most isn’t in a form plants can use, so it usually needs to be added. It is important, however, not to over-fertilize with phosphorus amendments because an excess of this nutrient can interfere with the uptake of others such as iron, zinc and manganese. The best way to take the guesswork out of what nutrients to emphasize at what time and how much of each to use, is to use a pre-mixed, balanced organic fertilizer. The lower concentrations also help avoid over-fertilizing.
Fertilizers supplement a soil’s native nutrient supply. They are essential to good plant growth when the soil nutrient supply is inadequate. Rapidly growing plants such as annual vegetable crops need more nutrients than slowly growing plants such as established perennials. You can use processed fertilizers that are refined from natural ingredients to make them more concentrated and more easily available to plants, or you can choose organic fertilizers that are natural biological or mineral materials. In general, you would need larger amounts of organic fertilizer, but the effects last longer in the soil, and an additional benefit is they recycle materials that otherwise would be discarded as waste.
Sources:
Sustainable Gardening: the Oregon-Washington Master Gardener Handbook, April 2013, pp 46-54
Backyard Bounty by Linda Gilkeson, 2018, pp 70-74
- What winter vegetables can I grow in my unheated greenhouse?
Unheated greenhouses are excellent for growing leafy greens (as opposed to root crops that are better outdoors under mulch). You can try Swiss chard, and salad plants such as lettuce, kale, spinach, parsley, arugula, mizuna and komatsuna. You can sow these crops under the summer crops or lift entire plants from an outdoor garden and transplant them in your greenhouse. These will work whether you plant in containers or into soil beds, but you may need to begin watering once the days get longer and brighter as early as February if the plants are in containers.
Ironically, if there is a cold snap with temperatures below -5 degrees Celsius and it has snowed, greenhouse plants may need more protection than outdoor ones. If it gets this cold or colder, plan to cover plants in your greenhouse with plastic sheets, tarps or blankets as it won’t be any warmer inside an unheated greenhouse than outside over a long winter’s night.
Source:
Backyard Bounty by Linda Gilkeson, 2018, pp 175-176.
Feb 2022
- I'm new to gardening on the coast. How do I take care of my dahlias in the fall?
Great question, Dahlia tubers are not fond of the wet coastal winters. They risk freezing, and too much water creating crown rot. All your time and money turned to mush.
On the coast Dahlia plants mature at 120 days and can be pulled any time after that (usually October). The longer the plant is in the ground, the longer it has to develop the roots. Some prefer to wait until the first killing frost as a guide. The timetable can be adjusted to suit you and mostly before our fall rains.
If you have a dry protected area that doesn't freeze & doesn’t get overly wet you “might” be able to overwinter some varieties in the ground but, you need to know your landscape (microclimate) and the dahlia varieties. Plus, take extra measures to protect the plants in case the weather goes through a deep freeze. For most of us, it’s safer to pull the plants.
Success rates vary about 90-95% based on variety, cultivar, growing season, and overall plant care. Before you lift the plant, inspect for productivity and plant health. Poor producers are not likely to do any better going through this process. Any diseased plants must be removed and thrown into the trash not composted.
Tools needed are a pitchfork, digging shovel, pruning shears, scissors, toothbrush, strong knife, and disinfectant. Ensure all tools are sharp and clean. Disinfectant can be a mixture of 10:1 of water and either bleach or peroxide. You can mix up disinfectant or purchase a commercial product & put it in a spray bottle for convenience. Consider using 2 pruners so one can sit in disinfectant while you are using the other. This part is very important as diseases (mosaic virus, leaf gall, crown gall) can easily move between plants.
Cutting the stalks. Cut the plant off leaving up to 6 inches of stem for both ease of handling and labeling. Stalks can harbor fungus and pathogens so keep what you need, no more. If you are unsure about locating the eyes for division, if time and weather permits, clip the plants off and leave the plant in the ground for a few days. Be sure to cover the stalk (tin foil works well) so water doesn’t get in. Leaving the plant in the ground helps to develop the eyes.
Label your tubers. Once a plant is cut off it is hard to tell them apart. Label them when you are lifting unless you don’t mind surprises in the spring. There are many ways you can label including wire tags, waterproof markers, having multiple labels in case or processing each variety at the same time as tall plants or yellows or pom poms. Consider all the processes they go through before planting again in the spring. Washing, dividing, storing in media can dislodge some tags. Check at the beginning and end of each stage to avoid frustration
Lifting out the plant. The neck is fragile requiring care when lifting. By digging one foot away on all sides, you can get the feeder roots ensuring less risk when pulling the plant out of the ground. Once the plant is removed from the ground you can carefully knock off excess soil, tip upside down to drain any water & leave for a few hours to dry and stiffen the neck.
Washing. The dahlia societies recommend washing the soil off allowing a thorough inspection of the tuber for existing & potential prevention of disease by removal of most microorganisms. In addition, having a clean tuber will allow for easier eye identification for division.
Drying the tuber is another reason why divisions in the fall are easier. As the plants are kept in storage, they get hard requiring more effort dividing in the spring. Once the tuber is washed, inspected, allow to dry for a day or so then divide.
Division (or splitting the tuber). Tubers can start from one and by the end of the season have as many as 10. The division is beneficial in both giving you more plants and doing extra inspections while making the bulk of your tuber easier to handle. You must locate the eye which will be on the new tuber at the top where it joins to the old or mother tuber. This is where you will cut it away from the mother. You can find pictorials and videos online by qualified growers to aid in this task. Cutting and storing a tuber that doesn’t have an eye is a waste, as is anything that has a neck smaller than a pencil, as it will likely dry out.
Once cut, treat the cut ends with a fungicide. You can reach out to your local garden centre for safe read- to-use products. Many will contain sulphur. If any mixing is required, always read the safety label follow the instructions. Another approach is to treat the dahlia division cuts with cinnamon.
Once divided & treated, place the tubers on racks for full air circulation and leave for 24-36 hours depending on the tuber size.
Storage. The ideal temperatures are between 4.44C-7.2C (40-45F) with relative humidity between 75-85. There are a few methods for storage each has pros and cons. The media that gets the highest ratings through my research is vermiculite (large particles).
Cling wrap requires constant cold temperatures and low humidity which is not great for on the coast unless you have some sort of special refrigeration. |Note about fridges. Newer models are built to remove humidity (frost-free) this is not good for storage unless you have a sealed container. Wood shavings can harbour fungus and pathogens and should only be used for a single season. Sphagnum moss being so dry can dry out the tubers so should be lightly misted before and monitored through the winter. Vermiculite (no longer contains asbestos & is now considered safe) can be used. Once you choose your media put it in a container (most use plastic like Rubbermaid or buckets with lids) that have small holes drilled on the body and lid to allow for air moisture exchange.
Monitor through the winter that they don’t dry out too much (they will start looking wrinkled). I peek every month or so and may use a mister on the media if needed. The following spring you can do divisions with the eye being more prominent.
For more information, we are very fortunate to have the Dahlia Society here in Victoria & the American Dahlia Association as well as professional growers. All have information published in print, online, social media and on YouTube to help you every step of the way. If you have questions about a particular tuber you can post the photo on FaceBook for assistance in assessing disease and more.
Be very careful though, Dahlias are addictive. Enjoy!
Sources
https://victoriadahliasociety.org/
https://victoriadahliasociety.org/2013/09/tuber-splitting-and-winter-storage
https://www.dahlia.org/growing/dahlia-university/
https://www.dahlia.org/docsinfo/articles/digging-dividing-and-storing-tubers/
https://link.springer.com/article/10.1007/s10658-019-01882-0
Thompson, Connie (2021). Connie's Dahlias: A Beginner's Guide. FriesenPress: Altona, MB
- Can I overwinter rosemary in pots on a deck?
Here on southern Vancouver Island, being approximately Zone 8, (microclimates may raise or lower your zone), Rosemary can overwinter in pots with some care and precautions.
First, choose the right plant. There are newer cultivars that are bred for better cold-weather hardiness. Some are Alcalde, Arp (most hardy & fragrant), Athens Blue Spire, and Salem which is fairly tolerant of moist soil. Ask at your local garden centre and they can point out the plants with the best hardiness.
Once you select your plant and know about its requirements such as water (drowning and then freezing is the worst), sun exposure, and cold hardiness, then get the best pot for the job. Select a pot that’s slightly larger than the plant’s root ball. Preferably a pot that is about 5 gallons. Anything less than that you have to go to many more preventative measures to ensure success during the winter. While unglazed pots work well to help evaporate moisture through their walls, they don’t fare well if we have a freeze tending to crack. My preference is a double-walled pot, either plastic or glazed, which would be labeled as Frost Free. This added air in between the layers will help protect the root ball if we do get freezing temperatures. Position the pot as close to the house as possible which will give it added protection from cold winds. Once potted avoid pruning at the end of the growing season as it could stimulate new growth which tends to tender.
If there is a cold snap predicted, providing extra layers of protection will be beneficial. You can wrap it with burlap and or put a shrub hut over it. This will not only protect it from freezing but will help if there is snow that tends to get heavy which could bend, even break branches. With pots, you can always bring them indoors (garage) if a patch of cold weather is coming through.
Now it is all about enjoying fresh herbs year-round.
Sources:
https://www.thespruce.com/herbs-for-containers-1761659
https://www.thespruce.com/grow-and-care-for-rosemary-plants-1403406
https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=b968
https://www.sunset.com/garden/flowers-plants/right-rosemary-for-you
https://forums.botanicalgarden.ubc.ca/threads/rosemary-herb-cold-hardy-for-vancouver.92695/
January 2022
- My pear tree has had fire blight this past spring but is still alive. How do I prune and manage it?
Fire blight is a destructive bacterial disease of pear, apple, hawthorn, quince, and mountain ash. Its occurrence depends on weather conditions and outbreaks in the vicinity. It’s a serious disease which kills leaves and branches and can kill the tree, especially a young one. The symptoms can appear in several parts of the tree: blossoms, shoots, leaves, bark and roots. Dead blossoms and leaves and shoots, oozing cankers on bark and discoloured cambium layers are symptomatic. Insects can transmit the infection to other parts of the tree from the ooze. Timely intervention is necessary to try to control the disease. There are live, beneficial inoculants which can be applied during bloom to help prevent fire blight from getting established. Fire blight overwinters in old dormant cankers in trees. Remove the cankers in winter dormancy making cuts 15-30 cm below the canker margin. Be sure to sterilize tools after each cut with a bleach solution of 1:5 or Pine-Sol. Current season infections should be cut out and disposed of but not composted. Cut out oozing cankers first. If there is an extensive infection there is another way of pruning called the “ugly stub” method. Instead of pruning to a healthy branch union, leave a 10-12 cm length stub. Mark the stubs with bright spray paint. Small cankers can appear on the stubs which can be removed during subsequent winter pruning. If fire blight is a problem, during the growing season reduce soil moisture as much as is necessary and reduce nitrogen fertilizer applications. Don’t run overhead irrigation when fire blight risk is high. Plant only non susceptible cultivars. Remove alternate fire blight hosts, such as hawthorn, mountain ash and pyracantha from the area.
Sources
https://www.bctfpg.ca/pest_guide/info/27/Fire_Blight
https://www2.gov.bc.ca/gov/content/industry/agriculture-seafood/animals-and-crops/plant-health/insects-and-plant-diseases/tree-fruits/fire-blight
- Could you tell me some plants that are blooming in fall? I’d like to have some pink colour.
There are several bulbs, perennials, shrubs and a grass which have pink flowers in the fall. Bulbs include Amaryllis belladonna (naked ladies), Colchicum autumnale (fall crocus), Nerine bowdenii, and Cyclamen hederifolium. A pink flowered shrub is the Abelia ‘Edward Goucher’. Here are 4 perennials with pink blossoms: Tricyrtis ‘Tojen’ (toadflax), Schizostylis (some pink), Japanese anemone (some pink) and Sedum spectabile ‘Neon’ . A late blooming grass called Mullenbergia capillaris has frothy pink inflorescence. Plan ahead to put in fall blooming bulbs when they become available. Ask around nurseries to bring in the other plants for you as they may not be widely available.
Sources
https://www.greatplantpicks.org/search/advanced (This site offers good growing information and photos of plants for the Pacific Northwest).
https://www.finegardening.com/article/pink-plants-for-fall
https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/visual-guides/perennials-for-season-long-bloom.aspx
https://www.rhs.org.uk/garden-inspiration/seasonal/plants-for-autumn-bedding
Dec 2021
- Edibles: Scarlet runner beans
I would like to plant scarlet runner beans along the wall of our house where a trellis with closely spaced narrow slats is attached to the wall but I am concerned the vines and beans will get trapped behind the trellis unless I continuously guide them out. Any suggestions as to how I can prevent this from happening?
Many will use a Pea and Bean Netting, which has a large weave of 12.5cm (5"). However, you could attach a smaller wire or net mesh on top of the slats. The plants flower from the top so you can pinch to create branches and yes, train to a certain degree.
Know that Scarlet and runner beans are known to require insect pollination (typically by bees) to set a crop. If the pollinators don’t see or find the flowers (on the backside of the slats) you likely won’t have the fruit (beans) set to grow on the back side of the slats.
As an interesting side note. Yield and seed quality of scarlet bean and runner bean is up to 10 times greater when insect pollinators are present, mostly the large-bodied bumble bees and carpenter bees. Honey bees will visit the flowers, but they do not seem to actively collect pollen or facilitate cross-pollination.
Sources
Free, J.B. 1993. Insect Pollination of Crops, 2nd edition. Academic Press.
Ibarra-Perez, F.J., Barnhart, D., Ehdaie, B., Knio, K.M., & Waines, J.G. 1999. Effects of insect tripping on seed yield of common bean. Crop Science 39:428-433.
Labuda, H. 2010. Runner bean (Phaseolus coccineus L.) - biology and use. Acta Scientiarum Polonorum-Hortorum Cultus 9:117-132.
- Planters for full sun:
I have a small patio with some large planters that sit on my railing as well as some smaller planters that would get a little less sun because they wouldn't be on the railing. My patio gets full sun for most of the day from morning until early evening and then it gets partial sun. I was wondering if you could make some suggestions about the types of plants that would work well and any tips or tricks for getting started?
You are very lucky to have so much sun! Even the plants that are not on the railing can still reap the benefit of your sun exposure position. You can chose perennials, or annuals, or a combination even including herbs. It is a matter of preference. For many they like to create their planter each year with a different colour theme that flowers spring thru fall. I have tried both. I found replacing all of the plants annually was costly for multiple containers. Doing a mixture can work well even leaving some hardy evergreen plants thru the winter. Creating the backbone with perennials then some annuals giving pops of colour for an ongoing succession of colour.
Design is considering colour, textures, size &, a bonus to include is fragrance! Think thriller filler& spiller. The tall plant is your thriller (e.g., Dahlia, Canna, Colossians, Lillie’s, Phlox, Agapanthus ). The filler hides the soil (e.g., Salvia, Alstroemerias, snap dragons, Agastache, Chives, Abutilon coleus) and the spiller weeps over the side (e.g., euphorbia marginata, oregano, ever bearing strawberries, dianthus). Note some plants have tall versions as well as small ones.
· For the baskets on the railing, I have been very successful with herbs such as oregano, thyme, chives, tarragon, basil, and savory to mention a few. In addition, strawberries can do very well in baskets. You can get an ever-bearing plant that gives you small amounts of fruit throughout summer. Anything shaded can have coleus, hostages, astilbe, ferns, & hardy geranium as they can take any light levels.
Many garden centres have planter recipes. Choose the one you like and they have the plants recipe ingredients to make it up. Creativity is easy with plants you can never grow wrong :)
Sources:
https://www.provenwinners.com/Container-Design
https://www.finegardening.com/article/thrillers-fillers-spillers
Goetz, S. (2021). Complete Container Herb Gardening: Design and grow beautiful, bountiful herb-filled pots. Beverly MA; Cool Springs Press.
Nov 2021
- I have bulbs in pots and wonder if I can plant them outside. I don’t think they will flower again in pots.
Some bulbs that have been forced to bloom in pots indoors are discarded when finished. The exception to this are narcissus (daffodils) and hyacinths as they are more vigorous bulbs. Cut off the dead flowers, water the pot regularly until the foliage is completely yellow. You can remove them from the pot, clean the bulbs and store them in a cool dry place for planting in the fall. Even easier, plant them from the pot right into the soil in spring after watering and foliage dies.
Most tulips are grown for one showy flowering then the bulbs start to deteriorate. The bulb puts energy into forming bulblets which rob the plant from having another good flower the next year. Many people plant tulips in pots as it’s easier to plant into a pot with bagged potting mix. Discard the soil and bulb or compost when they’re finished flowering in the spring.
There are tulip species which originate in the gravelly mountain soils of Turkey that rebloom and naturalise. Among these are the so-called species tulips, or botanical tulips. They are small and short but bloom early and last weeks. Plant in well-drained soil. Other tulips that rebloom in subsequent years are the Darwin tulips and the Fosteriana tulips. These don’t break into bulblets as readily as the other varieties. Their long growing season gives them time to recharge their energy for next season. A good garden catalogue will provide photos and information for growing and ordering. Most nurseries carry the regular one-season tulips so you’ll have to look further for the tulips which will rebloom in following years.
Other bulbs that can be planted in pots, then replanted to bloom outside for years, are narcissus. These sturdy bulbs are also deer resistant where tulips are not. Other spring blooming bulbs which can be potted and replanted for seasons of blooms are crocus, hyacinths, allium (deer resistant), snowdrops, winter aconite, scilla, muscari, and chionodoxa (glory of the snow). With all of these, water until the foliage dies, cut off the dead flower after the bloom has finished, dry and store, or replant outside. Don’t twist and fold the foliage; the plant needs to photosynthesize to energize the bulb. They won’t need much watering until fall. With our droughty summers we can let the potted bulbs remain planted in their pots and not watered until the seasonal rains begin. Our winters are cold enough for the bulbs to have their chilling period before breaking their dormancy in spring. You can drag the pots to a corner for the summer and fall, then arrange them out for a show in the spring. When you buy plants from a nursery, remember to save the gallon and larger size pots for planting.
Sources
https://www.extension.iastate.edu/mills/sites/www.extension.iastate.edu/files/mills/October%202012%20Plant%20Wise.pdf
https://www.dailymail.co.uk/home/gardening/article-2279147/Monty-Don-Hyacinths-forever-If-know-youre-doing.html
https://www.finegardening.com/article/planting-spring-bulbs-in-containers
Catalogues and sites
https://www.botanus.com/ordering/how-to-order
https://www.brecksbulbs.ca/
https://www.veseys.com/
https://www.vannoortbulb.com/
http://www.thimblefarms.com/
- What is the best type of mulch for strawberry plants which are planted in a garden bed? I have problems with slugs and other insects. I don’t have straw, but have used broken egg shells and coffee grounds. Would fine compost or wood chips help?
Slugs are a problem in garden beds and they will eat strawberry leaves and berries, leaving holes for other insects to crawl into to get at the fruit. There is no single remedy for the problem but a number of measures together can help. The right mulch can be helpful as well as patrolling the plants at night with a flashlight and picking the slugs off. Watering in the morning allows the night moisture level to drop. Copper tape applied around the plant causes a barrier as the metal reacts to the slime emitted from the slug and repels them. This can help as long as there are no slugs or eggs within the area. Eggshells can be useful by creating a rough surface slugs don’t like but the shells must be clean and dry. Watering and rainfall makes the shells soft. You can place old boards or damp newspaper on the ground at the side of the bed. Lift them up frequently to pick out the slugs hiding underneath.
Some people say coffee grounds are effective. A caution in using them is that they pack down and create a barrier to moisture and air movement. Fine compost has a similar effect while a coarser compost will benefit soil health. Drown slugs with a container of beer. Use a plastic food container with a lid and holes punched around the sides near the top. Set the container with the holes near ground level. Slug baits containing iron are effective. Sprinkle the granules sparingly over the bed and replace after a heavy rain. Baits that contain metaldehyde are poisonous to pets and wildlife. Wood ash and diatomaceous earth aren’t effective in our wet coastal climate.
A good mulch to use is wood chips (not bark mulch). Apply the chips around the plants on top of coarse compost. The coarse chips allow air and water movement in the soil and will help prevent the soil from drying out in warm weather. Any fungal species in wood chips will generally decompose. In healthy aerobics soils, beneficial fungi probably outcompete pathogenic ones. Reapply fresh chips after heavy rain.
Sources
Scott, Linda Chalker. (2007). Impact of mulches on landscape plants in the environment, a review. Journal of Environmental Horticulture, 25(4), 239-249. (https://gardenprofessors.com/wp-content/uploads/2010/05/JEH-254-239-249.pdf)
Glikeson, Linda A. (2011). Backyard Bounty: The Complete Guide to Year Round Organic Gardening in the Pacific Northwest. New Society Publishers.
October 2021
- Can you let me know when is the best time to repot my new Scarlett Sentinel apple tree?
The first question to ask is whether or not your tree needs to be repotted. Young columnar apple trees, such as the Scarlett Sentinel, should be started in a smaller container (about 5 gallons) and potted on into gradually larger and larger pots every two to three years until they reach its maximum height of about 2 to 2.5 meters, at which time it should be fine to stay in a container approximately 50 cm wide by 50 cm deep (25 gallons). However, if your tree has not reached its full height but vertical growth has stopped, it looks less healthy, if you see roots growing out the bottom of the pot, or if the soil dries out more quickly, you may need to “pot it on” sooner so that it does not become root-bound.
If you have determined that your tree does need to be repotted, the best time of year to do that in Victoria is in the fall. This will give your tree a chance to put out new roots prior to the tree entering dormancy over the winter, and will, in turn, ensure the tree has the infrastructure it requires to access what it needs from the soil in order to meet all the demands that spring places upon it.
Note that if your tree has reached it’s full size, it may still need to be repotted periodically, although not necessarily into a larger pot. Although the tree has reached maximum size, it’s root system will continue to grow. You will need to remove it from the pot and root-prune it every 2-3 years, or when you notice signs of it becoming root-bound. Use this opportunity to replace 30-50% of the soil in the container with fresh compost, to provide your tree with the nutrients it needs to remain healthy and continue producing a good crop.
Sources
https://www.rhs.org.uk/fruit/apples/grow-your-own
https://www.gardenersworld.com/how-to/how-to-plant-an-apple-tree-in-a-pot
https://dodge.extension.wisc.edu/2021/05/ask-a-master-gardener-proper-tree-planting/
https://www.finegardening.com/article/columnar-apple-trees-for-suburban-yards
https://apples.extension.org/apple-rootstock-info-m-26/
- This year we seem to have a lot of slugs in the garden eating our plants. We tried crushed eggshells and coffee ground. Also a solution of vinegar, water, and a little dish soap has not helped. Nothing seems to work. We don't like to use any chemicals. Do you have some ideas?
Although slugs do have bad reputation as the gardener’s nemesis, it is important to remember that they are an important source of food for frogs, birds, raccoons, beetles, ants, nematodes, and others. Outside of our gardens, slugs eat decomposing vegetation, so they do provide an important service in the overall ecology of an area.
In order to thrive, slugs require shelter from the elements and from predators, a moist environment, and of course a suitable food source. To help control their numbers, start by removing any debris from your garden that may be sheltering slugs (leaves, boards, rocks, etc.). Next, check your garden beds for any low spots that may be collecting excess water. While it is important to ensure your plants receive enough water to be able to thrive, overwatering can not only stress your plants, it creates a better habitat for slugs. Finally, note that “wild” slugs (those that reside outside our gardens) eat not only seedlings and new growth of herbaceous plants, but also decomposing plant matter. This latter item does provide a clue about how slug damage may be kept to an acceptable level. Weak or diseased plants will produce chemical reactions within their tissues that it is believed slugs can detect. It may be that the plants the slugs are attacking most are stressed or diseased, so if you are able to provide those plants with what they require to be healthy and grow strongly, the slug damage may be reduced.
If your existing plants are living their best life, planted in ideal conditions and kept free of disease and pests, you could try planting a few less-healthy plants at a distance. This may lure slugs away from the plants you are trying to protect. Another method that is commonly used is taking a flashlight and heading out into your garden after dark, which is when slugs are most active, and hand-picking them off your plants, to be either dispatched or rehomed. Some gardeners have found their slugs are rather fond of beer, and they take deep containers with lids, cut a hole in the lid large enough for a slug to get through, fill the container with about 2 inches of beer, and sink the container into their garden so the lid is at soil level. Slugs will make their way into the container. You will just have to remember to change the beer every few days.
Sources
https://www.canada.ca/en/health-canada/services/pest-control-tips/slugs-snails.html
https://www.rhs.org.uk/advice/profile?pid=228
https://extension.psu.edu/programs/master-gardener/counties/lackawanna/news/2015/slugs
September 2021
- I am confused about the "sucker" on tomato plants. I am afraid to clip the wrong thing on the plants. Could you describe these to me please?
The “sucker” refers to a side shoot. Whether it is necessary to prune or pinch them out will depend on whether the tomatoes that you are growing are “determinate” or “indeterminate” varieties. The label on the plant or seed packet that you purchased will indicate which type your tomato is.
Determinate tomato plants have a pre-determined size, according to their genetic make-up. They grow like bushes and need no pruning other than removing the leaves below the first flower cluster so that none touch the ground. They tend to ripen their fruit earliest, often all at once.
Indeterminates, grow like vines and will keep climbing and producing fruit until the days get shorter and the cooler weather arrives.
For indeterminate type tomatoes, little side shoots (suckers) sprout in the crotches, or axils, between the main stem and leaf branches as the plant grows (picture below). Each one of these has the potential to grow into a fruiting stem. Whilst this might seem like a good thing – more plant should mean more tomatoes; it is actually not good and may cause the plant to produce less fruit and be more vulnerable to disease.
Photo from Blog.gardeners.com
Ideally, limit the plant to no more than 3-4 stems. Remove all suckers below the first flower cluster and then allow the next two or three suckers above that flower cluster to remain. Remove any that appear above that as the plant grows. This will give you the 3 – 4 stems for fruit production. Gently pinch off, the suckers when they are small and easy to remove. They grow very quickly so it is necessary to check the plants frequently, preferably on a daily basis. If the suckers have grown too large to pinch then nip them out with a pair of sharp pruners, close to the stem but without damaging the stem or the leaf branch.
There are several reasons why it is important to do this type of” pinching out” or pruning:
1) Pruning tomatoes removes unnecessary leaves and suckers and provides better air circulation. A crowded plant will make it easier for foliar diseases and pests to spread because the foliage on crowded plants dries out more slowly, providing a perfect, damp environment for fungal diseases.
2) The tangled mass of foliage in an unpruned plant creates a lot of shade over the fruit. The ripening of the fruit will be affected and probably the size as well. Tomatoes need at least 7 hours of full sun exposure to grow healthy, ripe fruit.
3) When you prune unnecessary growth out of your tomato plants, the nutrients are directed to fruit growth rather than in aiding the development of foliage.
A note about “End of Season Care and Pruning”- By about the end of August, gradually start to withhold water, which stresses the plants a little and encourages the fruit already on the vine to ripen. Also, cut off any immature flowers and ‘cap’ the plant by cutting off the ends of fruiting stems. This way, the fruit on the vine will ripen, not having to compete with any new ones forming. There is limited growing time left at this point, and new fruit won’t have time to ripen.
Sources:
https://plantcaretoday.com/how-to-prune-tomato-plants.htmlhttps://russellnursery.com/articles/should-i-prune-my-tomatoes/https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/ec1333.pdf
- We are overrun by purslane in our garden. Could you please let me know if there is an easy way to get rid of it or is it a matter of pulling each little weed?
The first step is to be sure that the weed in your garden is definitely purslane as there are other weeds that are similar looking, such as Prostrate spurge which is a noxious weed.
Common purslane (Portulaca oleracea) is a member of the Portulacaceae family with more than 120 different species found in that family. It is a weedy summer annual species that is abundant throughout the world, invading vegetable gardens, bare areas, low-maintenance lawns, ornamental plantings, and agricultural areas.
Purslane has smooth, reddish, mostly prostrate (on the ground) stems. The leaves, which may be opposite or alternately positioned on the stem, are clustered at stem joints and ends. The yellow flowers are up to 6 mm (0.24 in) wide. Depending upon rainfall, the flowers appear at any time during the year. The flowers open singly at the center of the leaf cluster for only a few hours on sunny mornings. The tiny seeds are formed in a pod, which opens when the seeds are mature. Purslane has a taproot with fibrous secondary roots and is able to tolerate poor soil and drought.
Unfortunately, in home landscapes and gardens, Purslane is best managed the good old-fashioned and labour-intensive way by hand-weeding and mulching. Hand-pull purslane while it is still young. The key is to remove the weed from the soil before it begins to seed. If you don’t, the plant will “throw” seeds into the surrounding areas creating yet more weeding. Typically, each purslane plant covers a fairly large area so removing each plant clears an area fairly quickly.
Use caution when picking mature plants that have already begun to seed. Overturning the soil can bring other seeds up to the surface and cause the purslane to spread even more, so disrupt the soil as little as possible. It is important to remove plant fragments after weeding to prevent re-rooting. Place the plant matter into a paper or plastic bag before throwing it away. Stems and leaves can re-root themselves quickly, so if you leave any pieces laying around, you can expect to see more weeds growing soon.
If you are preparing a new area of the garden, cover the unplanted garden or ornamental area with plastic for 4-6 weeks. Do this during the hottest time of the year to prepare a bare area for planting. Ideally, you want the temperature underneath the plastic to reach 130 °F (54 °C). Use ground stakes or heavy rocks to hold clear or black plastic sheeting in place over the area. This process is called soil solarization and works to kill plants and seeds near the surface of the soil by heating them to extremely high temperatures and works best if the soil is moist.
Clean lawnmowers, trimmers, planters, and all garden equipment that has been used in an infested area before using them in un-infested areas. This will help prevent the purslane from spreading into new areas.
While it is considered an annoying weed by many gardeners, it does however have some redeeming features! As companion plant, purslane provides ground cover to create a humid microclimate for nearby plants, stabilising ground moisture. Its deep roots bring up moisture and nutrients that those plants can use, and some, including corn, will follow purslane roots down through harder soil that they cannot penetrate on their own.
Fun Fact - you can eat it!! Purslane may be eaten as a nutritious leafy vegetable. It has a slightly sour and salty taste and is eaten throughout much of Europe, the Middle East, Asia, and Mexico. The stems, leaves, and flower buds are all edible raw or cooked and Purslane has been identified as the richest vegetable source of alpha-linolenic acid, an essential omega-3 fatty acid.
Sources:
https://en.wikipedia.org/wiki/Purslane
https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=28193
https://www.ediblewildfood.com/purslane-identification-video.aspx
August 2021
- I bought a couple of garlic plants that are already plants. Do you think they will be able to be harvested this year?
Yes, you can harvest this year. Exactly when and what kind of crop you will get depends on when the garlic was planted. Typically, garlic is planted in the fall and harvested the following summer. While you can plant in the spring and harvest in late summer the same year, the bulb would not have had as much time to develop so it stands to reason that the bulb would be smaller.
Each leaf on the above-ground garlic plant represents one potential papery wrapper around the mature bulb. Having well-developed, fully intact wrapper layers means that garlic will store longer and keep its wonderful aroma and flavour. The trick is to let the plants begin to die back, but harvest before all the leaves have turned brown.
https://www.westcoastseeds.com/blogs/garden-wisdom/harvest-garlic
https://forums.botanicalgarden.ubc.ca/threads/how-do-you-grow-garlic-spring-planting.23240/?gclid=Cj0KCQjwxdSHBhCdARIsAG6zhlUj81qSrfiT_M2b-0TWrOqeNdv1PQkn5KAaqrZ7BedlZG49QUA-mMsaAl6SEALw_wcB
https://garlicseed.ca/blogs/growing-garlic/17725133-planting-garlic-in-spring
- I bought some Proven Winner Supertunias, starter plants. I have them growing as bought in my sunroom. When could I transplant them into pots and hanging baskets and put them outside? When would it be safe to do so with regard to the temperature being ok for them?
The rule of thumb to planting petunias has been to wait until the danger of frost is gone and night temperatures are consistently above 50f/F10C and the soil warms up (above 60F/15.5C).
However, Proven Winners trials have shown the supertunias are a bit cold hardier so can be started a bit earlier in the spring. That being said, if you have had them inside with very warm conditions acclimating them for a few days can only benefit them.
Sources:
https://www.provenwinners.com/learn/landscaping/ten-solutions-cool-weather-plantings
https://extension.umn.edu/flowers/growing-petunias
July 2021
- I have a 12” pot on my balcony and would like to grow a couple of tomato plants that produce small tomatoes. What would you suggest to best grow there? I have a sunny location.
There are literally too many tomato varieties to mention, but when selecting plants, you’ll want cherry or campari tomatoes, where the small fruits are born on trusses. Plant in fertile well-draining soil, and top-dress with 2-3” layer of compost. Whether bush or vine variety, you can plant within a tomato cage, or train the plant up a wall with ties or supports.
Pinch out the suckers that form in the angle of main stem and leaf stems. Use a liquid organic tomato fertilizer to increase yield.
A 12” pot is probably the minimum size to grow one plant. If you want more than one tomato plant, you will need more than one pot. Also, a 12" pot in a sunny location will dry out very quickly in hot weather, and will need regular watering. If you can shade the pot from the sun, or paint it white, that will help.
Sources:
Backyard Bounty (Gilkeson, 2018)
West Coast Seeds Gardening Guide
- I have a lovely Clematis montana. Underneath the blooms is a large and heavy load of dead vines. I would like to prune away the weight. When and how do I prune this dead wood without killing the plant? Will it bloom again next year?
Clematis montana is the most vigorous of the deciduous clematis species. Regular pruning (after flowering) is the best way to maintain the vine. Cut back unwanted shoots to a healthy bud. Remove weak or damaged growth.
If your plant is congested and heavy with woody stems, you can selectively remove certain stems. Or, if it needs a complete overhaul, you can cut everything away almost to the base. No matter your approach, be sure to keep the plant irrigated afterwards, and top dress with a good organic mulch.
Source:
Pruning & Training (Brickell & Joyce, 2017)
June 2021
- I am a relatively new gardener, living on Saturna Island. I have a number of Skimmia japonica shrubs growing as a foundation planting, mostly under some eaves, so in a tough place. I planted these shrubs two years ago, and they are doing sort of OK, have some flowers (yes I do have a male and 4 females), but look sort of leggy and not all that happy. I do water them some in the summer. I put a bunch of compost down earlier this spring but otherwise haven’t fertilized them. What do you think I should do?
Skimmia japonica are undemanding shrubs in good growing conditions. They require planting in fertile, moist, humusy, organically rich soil with good drainage, in deep or partial shade.
Planting under eaves suggests the shrubs don’t receive enough moisture. Skimmia like an average amount of water compared to other shrubs. The aspect they receive as to light may be another factor. Too much light will scorch the leaves and, due to weakness, may invite pests such as scale, aphids, or mites. These can be identified by closely examining the leaves for insects or damage and checking the internet for typical damage. The area where they are planted in may be poorly drained and they may have been planted in soil deficient in nutrients. Often, soil close to a house or building has been compacted and has little in the way of drainage. Another factor to consider is salt spray from wind, if you are close to the ocean.
Skimmia plants can be occasional tidied with a light touch but resent renovation pruning which is usually unsuccessful.
Our growing season has been affected by climate change. We are subjected to longer, drier summers and wet winters which dump a lot of rain over a short amount of time. Weather data from Environment Canada records very little rainfall from May through September on Saturna Island. Gardeners must provide water frequently during these months. A rule of thumb when watering is to water deeply and give time for each plant to take up water and the soil to drain before watering again. In warm weather this may be once a week for plants grown in the shade.
A general purpose fertilizer may help your plants but I suspect the planting location is the main problem. You could try digging up the shrubs in September and relocating them to a better location with good drainage and fertile soil.
Sources:
https://www.rhs.org.uk/Plants/17401/Skimmia-japonica/Details
https://www.timeanddate.com/weather/@6141341/climate (Environment Canada, Climate and weather averages for Saturna Island, BC.)
- I recently started planting vegetables last year in a home made cedar planter. The planter is roughly 2.5 feet above ground. I struggled really badly with earwig infestation! It was nasty in almost all my veggies I threw them almost all away. I did use a soap and water combo to kill them but I literally had to hunt and spray them. Can I please have any advice on how to kill and keep them away!
Earwigs are both pests and predators. Although they eat leaves, shoot tips, seedlings and decaying organic matter, their eggs are eaten by a range of insects. Earwigs are important predators of aphids, pear psylla, mites, and insect eggs. They help suppress wooly apple aphid, pear psylla and coddling moth infestations.
Earwigs feed at night and hide during the day. They shelter in leaves, old boards, under loose bark, and crevices on tree trunks. They feed on grass, vegetables, tree fruits, berries, ornamental trees and shrubs, and moss.
To control them, provide a hiding place of damp newspapers placed in an upside down cardboard box for them to gather at night. Shake them out into a bucket of soapy water in the morning where they will drown. Start using traps in May when they emerge from their nests.
Sources:
Home and Garden Pest Management Guide for British Columbia, https://www2.gov.bc.ca/gov/content/industry/agriculture-seafood/animals-and-crops/plant-health/insects-and-plant-diseases/home-garden/home-and-garden-guide
Earwigs/WSU Tree Fruit/Washington State University http://treefruit.wsu.edu/crop-protection/opm/earwig/#:~:text=Earwigs%20can%20damage%20both%20leaves,shape%20but%20with%20rounded%20edges
May 2021
- I am a new transplant to the West coast from Winnipeg. For the past five years I have tried to grow shelling peas in a variety of ways with no luck. What is the best place to plant peas? What is the best soil for successful pea plants? How often should I water peas? I hope to create the perfect haven for a pea bed!
Creating the Perfect Haven for Your Shelling Peas: Welcome to the West Coast! The best place to grow peas is in well-draining soil amended with organic matter like finished compost, that has not had legumes grown in the same spot for at least four years. You can fertilize with bone meal or rock phosphate at about 2 cups per 10m of row.
Choose a bright location that gets at least 6-8 hours of sun per day. They will tolerate some shade, but prefer, and will be sweeter, with full sun. If the leaves turn yellow in the summer, however, you may want to shade the plants during the hottest part of the day and ensure you are watering enough so they do not wilt. Before and while pods are developing, water them well. After that, as a rule, you’ll need less water than more and you can water sparsely, about 2.5 cm per week.
Create a trellis for them to climb and have it in place when you plant - the seedlings will need something to grab onto when they emerge. Peas climb best on string or wire, and don’t do so well on anything too smooth or wider than a pencil. Choose something sturdy, well anchored and wind resistant and avoid the soft mesh sold for peas and beans. Instead try woven wire fencing material or a section of stucco wire.
You may want to consider sprouting the seeds before planting them to help avoid losses to birds, rodents, slugs and other pests. Good luck and hope your harvest is bountiful this year!
Sources:
Backyard Bounty by Linda Gilkeson (2018) p. 104, 111-112, 125
https://www.westcoastseeds.com/blogs/how-to-grow/grow-peas
https://www.almanac.com/plant/peas
https://www.thespruce.com/how-to-grow-organic-peas-2540010
- My friend is digging out her mature rhododendron. I have a spot on my property for it. Is it worth trying to replant it or will the stress of uprooting it kill it?
Yes, you can transplant a rhododendron! Even large ones will tolerate being moved with proper care. The main things to consider are the roots that are shallow, fibrous and delicate, and you’ll want to get as much of the root ball as you can - dig wider than deep. As well, it sounds like you have a site in mind for it, and this should be a well drained, with rich organic and somewhat acidic soil in dappled light or part sun/part shade. Rhododendrons have a beautiful natural habit and shape and there should be enough space for the plant to mature with as little pruning as possible, if any.
You can transplant almost any time of year in our climate. The times to avoid are while the plant is blooming and then setting soft new growth post-bloom, and during the hottest part of the year.
Prepare the site first by digging a hole at least 2-3 times as big as the anticipated root ball and mix in about 50% organic matter. You can use partially rotted bark mulch, but compost, peat moss, or rotted leaves would also work well. The bark mulch takes longer to break down than things like compost, so is perhaps preferable for the initial planting. The aim is to have a fluffy, aerated soil with lots of organic matter.
To dig out the plant, try using a pruning saw to vertically cut around the root ball at the drip line (the area to which the outermost leaves grow) as this disturbs the roots less than using a shovel initially. For smaller plants, you may be able to lever the plant out with a shovel once the circumference has been cut. For bigger plants, you may want to dig a trench around the plant outside the initial cut and dig out underneath the rootball. Even for large plants the root ball is rarely more than 12-18 inches deep. You can then lever up one side of the root ball with 2x4’s, slide a tarp under, lever the other side up and pull the tarp out and then drag the plant with its root ball out using the tarp. Keep the tarp around the root ball while transporting it to its new location to preserve as much of it as possible. If you need to transport the plant by open truck, cover it with another tarp to protect the leaves from drying winds.
Water the plant every day for the first few weeks, unless it rains. Water a little directly on the root ball and then water in a circle at the edge of the root ball (drip line area) so that the roots are forced to stretch out to get to the moisture. After 10 days, just water at the rootball/drip line area with some sporadic watering directly on the root ball if the weather is extremely dry.
Sources:
http://www.fearing.ca/documents/howtoplantortransplant.pdf
https://www.rhododendron.org/transplant.htm
https://forums.botanicalgarden.ubc.ca/threads/moving-a-rhododendron.37682/
Videos:
https://youtu.be/yvxAukE0Bvo
https://youtu.be/AIvdgoej5p0
April 2021
- What is the planting depth for Hellebores? Can I plant my Hellebores in a long thinner planter? Will Hellebores reproduce in the garden?
Welcome Spring: Hellebores flower during late winter and spring and are long-lasting presence as the blooms that look like soft petals are in fact rugged sepals. Long after the blooms fade, the sepals remain in place lasting until early May. They are a staple of the spring garden rubbing shoulders with snowdrops and lasting until the tulips fade. Hellebores mix well with other spring-flowering woodland plants such as wood anemones and primroses; miniature bulbs including muscari, scilla, and miniature narcissi; or hardy ferns. The spring blooms are also very bee friendly, sustaining early bees fresh out of hibernation, so they are well worth growing for that reason alone.
Planting Hellebores: Hellebores prefer rich, well-drained soil and dappled shade close to deciduous shrubs and trees. They do not thrive in dry shade and do not like to be water logged. They can be planted in either acidic or alkaline soils in either the spring or early fall. Hellebores are deep rooted so dig your soil as deeply as possible, at least in a hole about 12 inches deep and wide, and mix in plenty of compost in the form of leaf mould, spent mushroom compost, or well-rotted manure. As they are hungry feeders, an annual top dressing of compost is of benefit. Trim off the leaves in early December to keep them disease free; as the buds open new leaves appear.
Planting in a Long Planter: Hellebore is best planted outdoors directly in the garden. However, if space is limited, it is possible to grow them in a container. As hellebores don’t like to be moved, it is important to choose a large container about 12 to 16 inches deep and as wide. The stress of the move can be damaging, so give your plant room to grow. The depth of the pot is particularly important as the roots mostly grow down. Hellebores need rich and well-drained soil, so be sure to choose a pot that drains and use a rich organic potting soil or add compost to existing soil. Hellebores can be pot bound when you buy them so tease open the roots to encourage them to spread and establish in the soil. As the blooms tend to droop downward, you may want to find an elevated spot for your container grown hellebore so you can fully enjoy it.
Reproducing Hellebores: Hellebores will produce seeds and self-sow but may result in unexpected combinations if you grow multiple types in close proximity. They are best propagated by division in early fall. Only divide the plant if necessary and then carefully split large clumps into large pieces with as many roots as possible and water in well. Newly divided plants will be slow growing and will take some time to become established and bloom. It’s best to deadhead after flowering in early May, because if your hellebore produces lots of seedlings year after year the mother plant loses vigour. Thin out seedlings that land too close to the mature plants.
Sources:
https://www.rhs.org.uk/plants/popular/hellebore/growing-guide
https://www.thespruce.com/growing-hellebores-in-the-garden
https://www.gardenia.net/plant-variety/helleborus-hellebores
- What is wrong with my McIntosh Apple tree? The bark is split on trunk and peeling. The fruit production has been reducing.
Crown Gall Disease: From your brief description I suspect your McIntosh is suffering from Crown Gall, which is a soil-borne bacteria that enter tree wounds caused by damage such as mower damage against the trunk, improper pruning, frost cracks, insects, or improper planting. As the bacteria are very common in soils since they affect so many plants, the Gall may have been present in the nursery soil when you first planted the tree. The bacteria stimulate the tree to produce hormones that cause the Gall to form and are most commonly found on the roots, low on the trunk near the soil line, but can also travel to the upper branches a distance from the actual infection. Crown gall interferes with the flow of nutrients and water along the stem or up the trunk affecting normal growth; your tree will start to decline and fruit production will certainly be affected. As well, your tree will also be more sensitive to drought stress or winter injury and the growths may eventually girdle the stems or trunk and kill the tree outright.
Unfortunately, there is no apple tree Crown Gall treatment that cures this disease. For young trees, avoid spreading other infections in your garden by removing the infected apple tree, including the roots; do not compost. Grow a non-susceptible plant such as grass for 3 years in that area, which virtually eliminates the bacteria from the soil once the infected tree is removed. If your tree is mature, you might try removing the Gall, and the bark tissue surrounding the Gall, which may result in some control given very good future care.
Apple trees are among the most prone to pests and diseases so looking at your trees regularly for changes or problems is not only a good idea, but is necessary. Planting apple tree varieties that are ‘disease-resistant’ is the first line of defense. Regular maintenance and simply observing the fruit trees’ progress, particularly during growing season, can help against apple tree pests and diseases before they get out of hand. If you do suspect a problem, research it online (a picture in this case is worth a thousand words), contact a local organization or garden center, or consider taking a workshop on fruit tree pests and disease - you will learn what problems to look for and how to deal with them when they are arise … and meet some fellow fruit tree gardeners to boot. It is reassuring to know that sometimes the solution can be as easy as just pruning and carefully disposing of a diseased branch, but not in the compost.
Improving Apple Production: Apples need care and attention, they are not a ‘plant it and forget it’ type of crop. Healthy, well-tended trees are more likely to produce an abundant, sweet harvest while neglected trees usually produce a small crop of disappointing fruit.
Plant Another Apple Tree: As most apple trees are not self-fertile and are incapable of setting fruit with their own pollen, at least one other apple tree is needed to act as a pollinator, even supposedly ‘self-fertile’ trees crop more heavily if another pollinator apple tree is present. Apple trees need a different apple variety nearby which flowers at about the same time, to allow cross-pollination to take place. McIntosh apples are a late-season apple ready for harvest in September so will need a mid-season apple variety to encourage pollination.
Pruning: All apple trees must be pruned every year to encourage fruiting, provide good air circulation, maintain shape, to rejuvenate mature trees, and for a long and healthy life. It is usual to prune established trees twice each year; ‘winter pruning’ spurs vigorous growth while ‘summer pruning’ is key to disease prevention.
Winter pruning during the dormant period between January to March allows the trees’ energy to be distributed to fewer branches so each branch will grow more and produce a better quality fruit. Remove dead, damaged, or diseased branches and those that cross-over, rub each other, or grow towards the trunk; remove limbs that come out of a trunk at a narrow angle as these develop weak crotches that may break under a heavy fruit load; and thin out water shoots. The tree will heal quickly and protect itself naturally from disease infections if the cuts are made clean and sharp and with disinfected hand pruners.
Summer pruning is undertaken to keep the tree compact and slow down the excessive growth of vigorous trees. Trees that shoot out several feet on each branch over the season are growing too fast. Some branches grow 4 feet or more each season, especially in a year they carry little or no fruit. Start pruning when the tree is no longer putting on new leaves at the tip of the branches; new leaves are smaller and a lighter green than mature leaves. This is usually around the end of July, although some trees put on new leaves until early August. Cut back branches by half and also remove water shoots and new shoots that are growing in the wrong direction.
Location in Your Garden, Planting, & Fertilizing: The ideal position for an apple tree is a sunny, sheltered site, well away from any late spring frost pockets. Avoid poorly drained or shallow soils. Apple trees should be planted in one area no closer than 12 feet apart and no further than 50 feet apart with no other trees or buildings in between. This helps insects pollinate the spring blossoms. Keep the area around fruit trees well weeded with nothing planted close to them that will compete for sun, water, or nutrition – no weeds, no flowers, no veggies, no shrubs.
Apple trees are often nitrogen deficient, so an organic source of nitrogen such as bone or blood meal or seed meals such as alfalfa or soybean meals will help them along. An apple tree should be watered deeply at least twice a week during the growing season as fruit trees can only absorb the nutrients in the soil if they are in liquid form, so dry soil leads to a malnourished tree. Concentrate water on the roots as apple trees are vulnerable to fungal diseases and excess moisture on the branches, leaves, or bark can make these problems worse. A soaker hose is ideal looped around the base of the tree so that the water can soak slowly into the ground and never use overhead sprinkler systems.
If you are going to plant another pollinator tree, you will see apple trees for sale in two forms; ‘bare-root’ stock (as the name suggests, the roots are exposed when you purchase these plants) or in containers. Bare-root trees should be planted from late autumn until early spring. Trees in containers can be planted at any time of year, though late autumn is preferred and always remove the container completely before planting. Keep the newly planted tree well watered and avoid fertilizing until spring. Before a new apple tree is planted improve the soil with well dug-in compost and continue with an annual application of compost or well-rotted manure around the roots in early spring. Most newly planted dwarf, semi-dwarf, or columnar apple varieties don't need staking. Even when staking is beneficial to a newly planted, tree say to straighten the trunk, it usually remains so for only a short period of time. Staking a tree that does not need it can do more harm than good as movement of the trunk helps strengthen and thicken it and encourages a wider spread of the roots.
Sources:
For a comprehensive list of apple varieties and their approximate ripening season see:
Kathleen Norris Brenzel ed., The New Western Garden Book, 2017, “Top Picks To Grow”, pages 157 – 159.
https://www.rhs.org.uk/apples
For clear videos of apple tree pruning see:
https://www.rhs.org.uk/advice/profile?pid=90
ttps://www.rhs.org.uk/videos/advice/Apple-pruning
For a complete illustrated guide to pruning apple trees see:
Christopher Brickell & Trevor Cole eds, Practical Guide to Gardening In Canada 2nd Canadian Edition, 2001, “Pruning and Training Techniques”, pages 373 to 379.
All the information for disease identification and treatment for the home gardener are attributed to:
Linda A. Gilkeson, West Coast Gardening Natural Insect, Weed and Disease Control, Appendix I: Table 5. “Common pests & diseases in the Pacific Northwest by host plant”, pg. 193 & throughout the book by type, 2013.
https://www.pnwhandbooks.org
https://www.bctfpg.ca/
https://www.gardeningknowhow.com/edible/fruits/apples/apple-crown-gall-treatment.htm
March 2021
- Can Virginia Creeper runners be cut back?
Yes, Virginia Creeper runners can be cut back. They are classed as pruning group 11 with the best pruning time in early winter or early spring each year to keep them under control. They will always try to reach their growth potential of 50 ft. by runners and underground rhizomes. Vines that have come detached will not reattach to a surface, so should be trimmed away, as should any dead or diseased vines. Take care with managing it and with disposing of unwanted material. The sap contains needle-like oxalate crystals, which can irritate the skin and cause a rash. If you are sensitive, wear gloves when handling it. If you like the look of Virginia creeper but are wary of its vigor, look for Parthenocissus henryana, or Silvervein Creeper. It’s much more restrained, and you still get that incredible fall colour.
Sources:
https://www.thespruce.com/taxonomy-of-virginia-creeper-2132897
https://www.rhs.org.uk/plants/12349/parthenocissus-quinquefolia/details https://forums.botanicalgarden.ubc.ca/threads/virginia-creeper-parthenocissus-quinquefolia.12795/
- I am thinking of building a raised bed for raspberries on the east side of our home (will be partially shaded as our neighbours house is 20 feet away). Do you think they will still produce in less than full sun?
Raspberry plantings are productive for five to 15 years, depending on berry type, soil and pest pressure. It is good that you are researching to select a site best for optimal planting life. For best results, plant in a sunny position for 6-8 hours daily. While plants can tolerate partial shade, yield and fruit quality may be lower. Ideally, site your rows running north to south so that they do not shade each other.
Raspberry flowers are self-fertile and pollinated by insects, so avoid a very windy site. Also, the fruiting side branches of some cultivars are very long and may break in the wind.
Sources
https://www.starkbros.com/growing-guide/how-to-grow/berry-plants/raspberry-plants/location
https://www.rhs.org.uk/advice/grow-your-own/fruit/raspberries
February, 2021
- A volunteer Garry Oak seedling, about 10-12 inches tall now, is located right next to my path and needs to be moved. Can I transplant it? Should I grow it on in a pot or put it directly into the garden?
The success of transplanting oak trees diminishes with age, and this is because of the tree’s taproot. Because you are already digging up and disturbing the small tree, it is recommended to find a permanent spot in the ground for it to thrive, rather than in a pot. Going into a pot will necessitate another transplanting in the future, when the tap root is even more developed and vulnerable. Garry Oaks, BC’s only native oak tree, will live for hundreds of years and become quite large, so picking the right place for this legacy tree is important. A tree 12 inches tall should transplant well enough, as long as you are sure to dig down deep enough, and try not to disturb the taproot. Prepare the hole in advance, making sure it is larger than the clump of earth you are carefully digging up. Do not amend the soil, but till if compacted. Several cups of soil from around a mature oak can be added to introduce beneficial mycorrhizal fungi. Once planted, mulch the planting area with leaves or chips, and water regularly for the first few years to establish.
Sources:
https://metchosin.civicweb.net/document/1751
https://goert.ca/gardeners_restoration/garryoak_trees.php
https://ohgarryoaksociety.org/wp-content/uploads/2019/05/Quick-Guide-How-to-Plant-Garry-Oaks.pdf
- My pear tree has stopped producing fruit. What can I do?
There are a number of factors that could be affecting your fruit production. Spring pollination is key to having a summer crop. Pear flowers are less interesting to bees than almost any other flower due to the low sugar content of the nectar. Having two pear trees in close proximity can mitigate this problem. However, if few or no pollinators are active when your tree is in bloom, no fruit will set. By encouraging beneficial insects and native pollinators in general, you increase the odds of timely pollination. Having said that, if a late frost follows the blooming period, the crop can be doomed. While some varieties of pear are self-fertile, most require another pear tree for pollination. If you only have one tree, it might be possible that whatever pollination system that worked before (via a neighbouring tree) has been disrupted somehow. Look at the tree itself - is it healthy? Trees under stress might forgo reproduction. The same can be said for trees experiencing rapid growth, which will put energy into growing taller rather than forming buds. An overabundance of nitrogen-rich fertilizer is often to blame, a common occurrence when the tree is located in or near a lawn. Your pruning regime also directly impacts fruiting. Pears develop on two or three year old wood, and older, so it is important not to over-prune. Conversely, the tree‘s spur systems will become congested over time, and regenerative pruning is required to thin these for ideal fruit production. There are a number of insect pests that can cause damage to pear trees. The best regime to control these is to a) wrap a sticky band around the trunk between October and February, b) spray with dormant lime-sulphur spray in late winter, and c) spray spring foliage with BTK, if larvae are actively eating the leaves. Good gardening techniques of mulching around the base of the tree, and removing diseased leaves and branches, will go a long way to giving your pear tree the best conditions in which to thrive.
Sources:
Natural insect, weed & disease control (Gilkenson, 2013)
Pruning & training (Brickell & Joyce, 2017)
The Harrowsmith book of fruit trees (Bennett, 1991)
https://extension.psu.edu/home-orchards-why-is-there-no-fruit-on-my-tree
January 2021
- Is there an electric blue iris I can plant beside my pond?
The iris with an outstanding electric blue colour is the Iris ensata Maize N Blue. This is a Japanese iris, easy to grow and is wet site tolerant. These iris are the last to bloom in late spring. They have large ruffled flat blooms, are 30-36” tall, and should be planted 2’ apart in full sun. If weather is dry in spring provide ample moisture up to bloom period. They benefit from compost amended to the soil surface yearly in early spring.
Bluestone Perennials stocks this vibrant coloured iris in spring ‘21. As this is a U.S. nursery you might have to ask a good local nursery to bring it in for you.
Sources:
https://www.bluestoneperennials.com/
B.C. Iris Society has links to other iris societies https://www.bcirissociety.com/
https://www.rhs.org.uk/Plants/9240/Iris-ensata/Details
- What are some nitrogen fixing plants I can grow around my kiwi vines? Which pollinator plants flower in June when the vines begin to flower?
Legumes such as peas and beans and clover are good sources of nitrogen for the soil. These plants form a symbiotic relationship with soil bacterial. Atmospheric nitrogen is converted to ammonium nitrogen which is released into the soil when the plants are chopped, mowed or tilled and left in the ground. Nitrogen is “fixed” in the nodules of the legumes and stored in the roots and used by subsequent crops. Among spring flowering pollinator plants are lupines, early blooming lavenders, borage, cranesbill geranium and geranium macrorrhizum, chive allium, sweet clover, salvia, ajuga, dicentra (bleeding heart), lilac, ceanothus and pieris japonica.
Sources:
https://www.thespruce.com/nitrogen-fixing-plants-2131092
https://www.permaculture.co.uk/articles/nitrogen-fixing-plants-microbes
https://www.finegardening.com/article/excellent-nitrogen-fixing-plants
https://www2.gov.bc.ca/gov/content/industry/agriculture-seafood/animals-and-crops/animal-production/bees/food-for-bees/bee-forage-plants
https://www.finegardening.com/article/the-secret-to-perfect-pollinator-plants
Dec 2020
- When do I prune my mock orange?
Philadelphus lewisii: Mock Orange is BC’s native shrub in the Hydrangea family. Note that there are other species commonly referred to as mock orange or Mexican mock orange such as Choisya ternata or Choisya x dewitteana 'Aztec Pearl”. To be sure, we’ll cover both with the native species first.
Philadelphus lewisii is a deciduous shrub that flowers on the previous year’s wood. Pruning immediately after flowering will insure blooms next spring. They benefit from some regular pruning, usually just to shape. This light pruning will help keep the plant more dense and full. Every few years it is beneficial to do a rejuvenating prune by cutting a quarter of the older branches to the ground. This will open up and freshen the plant and allow for maximum bloom (in a similar way that is recommended with hydrangeas).
Chosiya species from the rue family, Rutaceae and its varieties, are early flowering evergreen shrubs (pruning group 8). Prune immediately after flowering usually in the spring.
Shorten stems by 25-30cm after flowering to encourage a second flush of flowers in autumn. Careful to not go later than fall so you don't lose next year's flowers.
Sources:
https://www.gardenia.net/plant/philadelphus-lewisii
http://linnet.geog.ubc.ca/Atlas/Atlas.aspx?sciname=Philadelphus%20lewisii
https://www.rhs.org.uk/advice/profile?pid=168
- My blueberries did not produce fruit this year. I noticed webbing around where flowers had been. What could have caused this?
Webbing usually indicates the presence of Spider Mites, including Two Spotted Spider Mite (Tetranychus urticae). Infestations are particularly common during hot, dry summer weather. They live through the winter as eggs on vegetation. Larvae hatch and complete development in 1-2 weeks depending on the temperature. Under high temperatures (>90°F), colonies can reach high numbers in less than two weeks. After hatching, the mites build colonies on the undersides of leaves and produce webbing over infested leaf surfaces. This webbing gives them the name "spider" mites. Plants can have a stippled and discoloured appearance and can even die with a heavy infestation.
Examine plants for stippling and/or webbing. Look closely with a hand lens on the underside of discoloured leaves for the presence of spider mites. You can also hold a white piece of paper or cardboard underneath potentially infested leaves, shake the leaves, and look for spider mites that have fallen.
Check garden plants every 3-5 days, especially under drought conditions. Keep plants healthy as Spider mites thrive on plants under stress. Keep plants well-watered to reduce the chances of a spider mite attack. Most plants should receive about one inch of water a week to avoid stress conditions. Conserve moisture through proper mulching. Do not fertilize plants during drought, as this can add further stress to plants.
Spraying plants with water disrupts colonies and slows down population development. Environmentally- friendly products for mite management are available, including insecticidal soap and dormant or summer oils. Check product labels for use instructions and to ensure the crop and pest are listed and observe instructions. Predator mites naturally occur, and can also be purchased to be released onto infested plants.
Sources:
https://extension.umn.edu/yard-and-garden-insects/spider-mites
https://www2.gov.bc.ca/assets/gov/farming-natural-resources-and-industry/agriculture-and-seafood/animal-and-crops/plant-health/gardenguide-11-berries.pdf
November 2020
- What is the difference between Salvia elegans and Salvia gesnerifolia?
In describing both plants, there are several similarities. Both originate in the Mexican Sierra Madré Occidental Mountains between elevations of 7,500 ft. to 10,000 ft. In the wild they grow larger than in cultivated gardens. Both have woody stems, green, ovate, hairy and fragrant leaves. Flowers are 2 lipped and tubular, and are popular with birds (hummingbirds, in particular), bees, and butterflies, and bloom late in the growing season. Both salvias require good drainage and dislike winter wet. The plants are fast growing, and heat and drought tolerant. Both salvias are deer and rabbit tolerant.
Gardeners in our area will be more familiar with salvia elegans, or pineapple sage. It grows in zones 8a to 11b (the larger number would be a heated greenhouse rather than outside). Container grown plants can be overwintered inside but outdoor growing ones could be considered annuals if there is a hard frost. In mild climates like ours it may overwinter. The height pineapple sage grows is 12-18 inches and width is 16-20 inches. A cultivar of pineapple sage has light green-yellow leaves and would benefit from a little afternoon shade in hot areas. Flowers are up to an inch long, arranged in whorls around the stem.
The salvia gesneriflora is a taller and wider plant in cultivation, growing 5-6 ft. tall and 3 to 4 ft. wide. Flowers are 1.5 inches long and have dark calyxes in the popular red flowered Tequila cultivar. There are pink flowering gesneriflora with green calyxes. This salvia is dramatic and an aggressive grower. It is not one I have found being grown for sale in our area. It is a popular plant in some Australian and Californian gardens and needs to be protected from strong winds and rain, likely why it wouldn’t do well in our wet winters.
Sources:
http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.as...
https://www.rhs.org.uk/Plants/Search-Results?form-mode=true&context=b%3D...
https://www.provenwinners.com/plants/salvia/pineapple-sage-salvia-elegans
https://wimastergardener.org/article/pineapple-sage-salvia-elegans/
- Is it possible to grow peaches in this area?
Peaches can be grown over most of BC, even north of Prince George. Finding the right variety for the area is key. In the north, a hardy variety would be necessary.
Peach tree growing is much easier with compact trees using dwarf root stock. A smaller sized tree can be more easily pruned. In our wet winters, the trees should be grown on a south wall with an overhang to protect from winter wet. Prune the branches so they fan out horizontally against the wall. Make sure to stake the tree and leave the stake for the lifetime of the tree. Aim for slow, continuous growth and regular water during the dry season. Peach trees are self pollinating. A common disease that can attack peach trees is peach leaf curl, a fungus. The trees should be sprayed with lime sulphur spray after most of the leaves (90%) have fallen then again in very early spring before the buds begin to swell to reduce the level of infected peach curl fungus spores. Grow the tree with good drainage to the roots, avoiding poor and compacted soil and drought conditions with correct watering. A U.B.C. gardening forum lists Empress and Frost varieties as successful in south coastal B.C. For advice on growing, contact Fruit Trees and More, nursery and demonstration garden in North Saanich. The B.C. Fruit Testers Association is another local resource with publications and a library.
Sources:
CBC news Brian Minter March 18, 2016
Fruit Trees and More 724 Wain Rd. N. Saanich, Bob and Vera Duncan https://www.fruittreesandmore.com/
https://forums.botanicalgarden.ubc.ca/threads/dwarf-peach-tree.150/B.C. (UBS Botanical Garden)
bcfta.ca (Fruit Testers Association)
October 2020
- Are rhubarb and swiss chard in the same family?
Despite their similar appearance, rhubarb and swiss chard are from different families, but do belong to the same order, Caryophyllales. Rhubarb belongs to the Family Polygonaceae, Genus Rheum, whereas Swiss chard belongs to the Family Amaranthaceae, Genus Beta.
Rhubarb is a perennial, and in the same family as buckwheat and knotweed. Swiss chard is an annual, and related to beets, spinach, and quinoa.
Source:
University of Maryland Extension (extension.umd.edu)
- What plants would be suitable for large rooftop balcony boxes? Evergreen shrubs have failed several times. Would bamboo be appropriate?
When considering what plants to install in rooftop boxes, we must first consider the conditions. Rooftops are artificial environments, and by and large they are completely exposed to the elements of sun, wind, rain, and drought. They are hot and dry in the summer, wet and windy in winter. A balance must be struck between these opposing elements to achieve rooftop gardening success.
Other factors to consider include irrigation and drainage. Very few plants will be happy going all summer without a drink, while those who prefer it on the dry side will not appreciate having their roots soaking all winter. Regular watering and well-draining soil are important factors when planting, and may vary between your containers based on what you decide to plant. The containers should be deep enough to allow good drainage and root development.
If coniferous evergreen shrubs failed, it is likely they lacked sufficient water through the summer. If broadleaf evergreen shrubs failed, it could be the same problem, or that they were better suited to shade. Bamboo is certainly an option for rooftop boxes, but they do require regular irrigation for optimal growth. Rooftop wind also contributes to desiccation. The key lesson here is that the hot summer drought is the most challenging aspect of life on a rooftop, so you will have the most success with plants that thrive in dry, sunny sites. Here are some suggestions for our climate:
Succulents and cacti like echeveria, stonecrop, agave, yucca, and prickly pear; herbs like rosemary, lavender, sage, oregano, cilantro… (most herbs really); flowering plants like agapanthus, armeria, artichoke, dianthus, eryngium, euphorbia, geraniums, lavatera, nasturtium, rudbeckia, salvia, and yarrow; and shrubs or small trees like berberis, callistemon, cistus, feijoa, fig, fremontodendron, grevillea, and olive.
This is a diverse yet quite incomplete list. Many more plants may very well thrive atop a roof, even sun-loving summer vegetables. However, care must be given to the specific watering and soil needs of each plant.
Sources:
Vermeulen, N. Encyclopedia of Container Plants, Whitecap Books, 1998
Ferguson, N. Right Plant, Right Place, Bookmart Ltd., 1997.
The Essential Gardening Encyclopedia, Fog City Press, 2003.
Sept 2020
- What are the best houseplants for low light conditions?
As with choosing plants for outdoor locations, it is important to choose the right plant for the right location indoors. Low light levels indoors are typically found on windowsills facing north or north east or in rooms or hallways away from natural light sources. Typically minimum winter night temperature should not fall below 10C (50F) and plants should be allowed to partially dry out between waterings.
Common small plants that tolerate low light levels include some indoor ivy (hedera helix ‘Duckfoot’), African violets (Streptocarpus), Peperomia obtusifolia, Soleirolia soleirolii, prayer and herringbone plants (varieties of Maranta leuconeura) and Swedish ivy (Plectranthus verticillatus).
Medium to large plants that tolerate low light levels include Begonia rex cultivars, Bromeliads, Diffenbachia, Ficus benjamina, Philodendron scandens, Sansevieria trifasciata, and Schefflera actinophylla. Other less common indoor plants that tolerate low light levels also may be available through your local nurseries.
Source:
https://www.rhs.org.uk/advice/profile?pid=947
- What herbs/flowers can I plant near my residence to keep deer away?
Good question! First, let’s be clear, there is no such thing as a deer-proof plant. However, there are many plants that deer tend not to enjoy and so avoid. As a general rule, there are a number of characteristics of plants that deer to not like. These are things to keep in mind when selecting plants. They include: fuzzy or hairy foliage on plants, plants that contain toxins that deer cannot tolerate, plants that have highly fragrant foliage, plants with thick, leathery or fibrous foliage or those with spiny or prickly foliage or stems, and ornamental grasses because they find them difficult to digest and have sharp edges.
So, which herbs and flower have these characteristics? Here are some choices,
Fuzzy or hairy leaves: lady’s mantle (Alchemilla mollis), Siberian bugloss (Brunnera macrophylla), ageratum, spirea (Spiraea), and yarrow (Achillea).
Toxic plants: Poppies (Papaver), false indigo (Baptisia australis), bleeding hearts (Dicentra), spurges (Euphorbia), hellebores (Helleborus), daffodils, and monkshood (Aconitum).
Fragrant foliage: Most herbs including mint, sage, thyme, rosemary, oregano, lavender and others including Russian sage (Perovskia), catmint (Nepeta), blue mist shrub (Caryopteris), and ornamental sages (Salvia).
Thick, leathery or fibrous foliage: Iris, arrowwood viburnums (Viburnum dentatum), pachysandra, peonies, barberry, globe thistle (Echinops ritro) and bear’s breeches (Acanthus mollis).
Even some vegetables with these same characteristics are unpalatable to deer: onions, and members of the cucumber and squash families. Many of these plants will do well in sunny locations. If you are seeking plants for a shady location you might consider bleeding hearts (Dicentra spectabilis) or Astilbe.
Sources:
https://www.rhs.org.uk/advice/profile?pid=185, Outwitting Deer by Bill Adler Jr., https://www.almanac.com/content/deer-resistant-plants#:~:text=Daffodils%2C%20foxgloves%2C%20and%20poppies%20are,just%20%E2%80%9Cstinky%E2%80%9D%20to%20deer, https://archive.triblive.com/news/repelling-deer-in-the-yard-is-as-simple-as-the-plants/
August 2020
- I have a shady spot under a cedar where I would like to put plants. What choices do I have?
Planting under Cedar trees presents challenges like root competition, acidic & dry soil in potentially deep shade. These challenges can be overcome and in fact working with what you have can provide you with a lovely woodland setting. Just remember the right plant right - right place comes into play as each garden will be different.
Speaking from experience I plant under a Cedar that is not twenty feet away from a Douglas Fir (planted by nature 75 years ago). While I can’t produce lush Astilbes, they will survive & even give me some flowers provided I keep my irrigation system consistent in the summer. Some plants struggled for nearly three years and this year was the pay off. So providing a nice hole with good soil, mulching (continuously build the soil & provide nutrients), and deep watering will give the plants a chance to develop their root system over time. Depending on how high your tree canopy is will determine shade levels and ultimate flowering ability of the plants. Here is a list of some that have done extremely well and some that haven’t but might work for you.
Astilbe
Aucuba japonica ‘Variegata’
Brunnera marcrophylla ‘Jack Frost’
Cyclamen hederifolium (hardy cyclamen)
Epimedium (bishop’s hat)
Gaultheria Shallon (Salal) - be careful, this can crowd out other plants.
Hakone grass (Japanese Forest Grass)
Hostas
Hellebores
Lamprocapnos spectabilis (Bleeding Heart)
Lamium (Dead-nettles)
Lonicera (Honeysuckle Species)
Maiden Hair Fern
Mahonia nervosa (Low Oregon Grape)
Polygonatum biflorum (Solomon Seal)
Polystichum munitum (Western Sword Fern)
Sarcococca hook. var. humilis – (Sweet Box)
Sambucus (Elderberry)
Skimmia japonica
Vaccinium parvifolium (Red Huckleberry)
Vaccinium ovatum (Evergreen Huckleberry)
Vancouveria (Inside-out Flower)
This list only scratches the surface of what you can grow under your cedar tree. Nearly forgot that I have lovely mature Rhododendrons who appreciate the shade and don’t mind it being on the dry side. What I have found with my garden is I research like crazy then go to my local garden centre and get taken away by the sights and smells in the shade area. The key for me is how much water is required (yes, I have irrigation but not everyone is happy about the water bill) and the ultimate size. For you it might be evergreens, whatever that is, know that you can have a fabulous garden under your Cedar tree.
Sources:
forums.botanicalgarden.ubc.ca/threads/what-to-plant-under-cedar-trees.13156/;
https://www.thespruce.com/tips-for-planting-under-trees-4119908; gobotany.nativeplanttrust.org/;
https://extension.oregonstate.edu/gardening/flowers-shrubs-trees/drought-tolerant-plants-shade
- Why don’t I have a lot of asparagus to harvest through the years?
Asparagus is a fabulous vegetable that requires an investment in time along with energy & neglect. For the best producing plant you need to provide a SUNNY location getting full sun (8+ hrs). The soil should be a rich well-drained sandy loam. Amending the soil with compost, manure, and minerals annually will help provide nutrients as it is a heavy feeder. Asparagus prefers a pH of 6.5 or higher, though it tolerates a pH in the range 4.3 to 8.2 Plants are male or female. Since males do not have to expend energy in producing flowers and fruit and typically produce better crop yields. There are cultivars that are specifically male (Jersey Knight). Then plant at the right depth so the crown has at least 2-3 inches covering of soil. Once you provide the best environment, then provide some neglect by allowing the crown roots to develop 2-3 years before you harvest. Rule of thumb is never harvest anything that is the size of a pencil or smaller. Keep in mind that each plant does not produce all at once so you will need multiple plants per person to provide meals for a family. Well-tended plants can be long-lived -an asparagus bed can last for well over 20 years.
Sources:
http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=263142&isprofile=0&chr=19 ;
https://pfaf.org/user/Plant.aspx?LatinName=Asparagus+officinalis;
https://oldworldgardenfarms.com/2020/01/19/how-to-grow-asparagus-keys/;
https://www.westcoastseeds.com/blogs/how-to-grow/how-to-grow-asparagus-crowns
July 2020
- My rose leaves this year are red unlike last years’ leaves which were green. Why is that?
Early growth of roses leaves are reddish and if they develop normally into healthy green leaves all is well. If you notice these symptoms then there is a problem: thicker, reddish stems which have a succulent feel and more thorns than usual (either red or green), small lateral branches growing excessively combined with reduced flowering and distorted petals, and profoundly affected plants having a red thready growth on the plant called witch’s broom. These symptoms start in spring and progress through summer.
The problem is caused by a tiny mite called Phyllocoptes fructiphilus. The mites infect the rose while feeding with a virus called rose rosette virus, or RRV. This disease is a serious problem in a wide variety of roses and the only solution is to dig out the plant including roots, bag and dispose it, and disinfect tools after using them. Observe other roses nearby and at the first sign of the virus infecting nearby plants dispose of them also as wind can carry the virus. There is no spray herbicide available for sale in Canada for this particular mite. Rose growers and breeders need to develop cultivars resistant to the virus as it is the best way for effective control.
Sources:
Rose Rosette Disease: Can you prevent it? https://www.finegardening.com/article/rose-rosette-disease-can-you-prevent-it
Clemson Cooperative Extension Home and Garden Information https://hgic.clemson.edu/factsheet/frequently-asked-question-about-rose-rosette-virus/
Featured Creatures Entomology and Nematology University of Florida http://entnemdept.ufl.edu/creatures/ORN/ph_fructiphilus.htm
- What can I do with all the weeds that come up in my raised beds over the winter?
After plants you have grown in the summer are finished and pulled out, the soil is filled with seeds that now have light to grow and a chance to germinate. Weed seeds can last for many years and only need the right conditions to flourish. In our coastal climate we have weeds which prefer a cooler time of year to germinate, flower, and disperse.
Several methods can reduce the weed population from growing. Planting vegetable plants close together during the growing season discourages seeds and weeds from coming up. You can cover your beds with mulch such as leaves and straw in the fall. This will also keep soil from wind erosion. Avoid tilling the soil. Instead, hand weed correctly and avoid deep digging and tilling, which will bring to the surface many weed seeds. If you prefer to use a hoe, scuffle the surface rather than deeply chopping. In the spring, lightly cultivate the beds, allow weeds to germinate for 1-2 weeks, then cultivate again. Repeat several times so that the number of weed seeds are greatly reduced. Deep cultivation the first time then subsequent shallow cultivation avoids bringing up deeper lying seeds each time. Avoid putting weeds with seed heads into your compost or use a separate bin that does not end up on your raised beds. If you buy compost make sure it is very well composted. Manure has a high number of weed seeds.
Source:
Gilkeson, L. A. West Coast Gardening Natural Insect, Weed, and Disease Control, Second Edition 2013
June 2020
- What type of fertilizer should I use for a Lemon tree?
Growing citrus, already a specialized area of horticulture, is made even more challenging in our climate. We live in what is essentially the northern limit of viability for growing the hardiest of sour citrus (namely limes, yuzu, and Meyer lemons) and even then it is only possible with a bit of winter protection from overnight temperatures below -3c. For more information and tips, watch local expert Bob Duncan’s YouTube video on growing lemons.
Generally speaking, citrus trees primarily require nitrogen on a regular basis, while phosphorus and potassium do not need regular replenishment (this may vary depending on if your tree is in a pot or in the ground; a soil test may be required). The first 2-3 years are nonbearing for citrus trees, and they require adequate nitrogen to encourage growth. The optimum rate is 1/10 pound per year for a 1-2 year old tree; this equates to a tablespoon every month over the root area, watered in.
That rate can be doubled (1/4 pound) for a 3-year-old tree, and up to a ½ pound for a 4-year-old tree. If your tree is not putting on significant growth to warrant such increases in nitrogen fertilizer, the amount used should be scaled back according to the size of your tree. Start application in the spring, and lemons respond well to continued application during the summer months with proper watering. Using slow-release vs. water-soluble fertilizer will dictate the frequency of application.
Compost and manure are also recommended, however it is important to note that manure can have a high salt content which can burn leaves, so should be well-rotted and used sparingly, avoiding too much chicken or steer manure. Also, the ideal pH of the soil is around 6.0-7.5. There are numerous mineral deficiencies that may cause foliar or fruit damage (iron, zinc, magnesium, phosphorus, potassium, and boron), all with their own symptoms and solutions.
Your local nursery will have citrus-specific fertilizer products that will help to simplify the feeding of your tree. Please contact Victoria Master Gardeners with specific questions and issues regarding your tree. We hope you enjoy growing lemons in Canada!
Source:
California Master Gardener Handbook (U of C, 2015)
Backyard Bounty (Gilkeson, 2018)
- How do I get rid of broom?
The smallest of young plants can be pulled up during the rainy season, but care should be given not to leave too much disturbed soil, as there are plenty of broom seeds ready to take advantage of that, and they can remain viable for decades.
The most effective and organic method is to cut it out when blooming. “Cut broom in bloom” is the best way to eradicate the invasive shrub, because as the plant is fully engaged in growth and reproduction, it is most vulnerable to being cut off from its roots. Plants too big to pull should be cut off at ground level in spring. It is important to cut right at the base, where the single stem emerges, and not miss side shoots.
Once removed, an area once infested with broom would benefit from a deep, smothering mulch of leaves, as well as planting native species or desired garden specimens.
Broom in seed should not be cold-composted, but rather bagged or burned. There are local groups dedicated to removing broom with the support of local municipalities and ministries. Visit Broombusters to learn more!
Source:
The Ann Lovejoy Handbook of Northwest Gardening (2007)
Invasive Species Council of BC (https://bcinvasives.ca)
Broombusters (http://www.broombusters.org/how-to-cut-broom/)
May 2020
- The leaves on my rhododendron are turning yellow. What is causing this?
To give you a specific answer we would need more information about your plant including: age of the plant, placement regarding sun, soil ph, actual leaf colour (totally yellow, green underside, green veins, brown edges), are the leaves dropping, and more. If it is simply all the leaves have turned yellow (above & below) and are remaining on the plant. We need to address a few things.
Age & Type of Rhodo: Yellowing and dropping of leaves is normal toward the end of the second summer on the small-leaved lepidote rhododendrons. These should have dense enough habit that this doesn't matter. The larger-leaved elepidote rhododendrons keep their leaves for 3 or 4 seasons. Like all evergreen plants, rhododendrons and azaleas periodically lose some of their foliage, and the leaves may turn yellow, red, or purple before they fall. Often the only leaves that remain are those that surround the flower buds at the tips of the branches. This characteristic is linked to the genetics of the parents used to breed garden azaleas. The degree of leaf coloration or loss is a function of parentage and not the severity of the winter. In unusually cold winters, certain azaleas may lose more leaves than they would in mild winters.
Placement: Wind & Sun - Leaves can become sunburned appearing yellow & scorched. They need some protection from the drying wind and the hot sun.
Drainage: Too much water can cause yellowing of leaves. They shouldn’t be planted too deep.
Water: Too little water can cause leaves to yellow. They need regular watering especially during hot and or dry weather.
PH: They need acidic soil with a PH of 4.5 to 5.5 Alkaloid soil can cause yellowing. Mulching with pine needles can help maintain an acidic soil (long term). However, to repair and ensure your plant enters winter as healthy as possible a soil acidifier can be done in the fall.
Fertilizer: Lack of food – Nitrogen and minerals can cause yellowing. Too much so can cause the same effect. Rhodos should be fed in late May or June after flowering. Inorganic fertilisers can respond to the need for nutrients faster than organic.
As Master Gardeners we recommend a holistic natural organic approach of pine needles and organic mulch maintained throughout the year. Note that all manures should be well composted and mixed with untreated sawdust or straw so they don’t burn the roots. Reacting to a problem you may need to reach outside the tool box for a quick fix but it is then recommended to keep the plant vibrant do as nature intended supply natural food. A well maintained plant suffers less disease and pests.
Source:
https://www.purdue.edu/hla/sites/yardandgarden/interveinal-chlorosis-on-azaleas-and-rhododendron/
http://www.frasersouthrhodos.ca/non-disease-problems/
http://rhodyman.net/ (all references listed on site)
- What is the difference between Lavender Augustifolia and Munstead? (May 2020)
Lavandula angustifolia is the species and typically grows to 1.5-3ft. Munstead is a cultivar (cultivated variety) of this. The proper name being Lavandula angustifolia 'Munstead' and as a cultivar of Lavendula augustifolia it is more compact, growing 12-18” compared to the species. An early-flowering English lavender cultivar that was first introduced into commerce in 1916. Munstead’ was reportedly named for Munstead Woods in England where the plant was grown by garden designer Gertrude Jekyll (1843-1932).
Source:
https://www.missouribotanicalgarden.org/things-to-do/events/special-exhibitions/foodology/articleid/91/herbs-heirlooms-lavender-lavandula-angustifolia.aspx
https://www.lavenderconnection.com/
April 2020
- Should a Nandina domestica be pruned?
Yes, but Nandina domestica typically needs little pruning. As with pruning any evergreen shrub, begin by pruning out any diseased, damaged, or dead shoots using secateurs or long-handled loppers. Then remove any unsightly, crowded or badly positioned shoots to enhance the overall appearance of the Nandina. Older branches can be cut down to ground level. Pruning should be done in mid- to late spring.
Source:
https://www.rhs.org.uk/plants/11327/Nandina-domestica/Details
- Can you grow a Red Elderberry (Sambucus Racemosa) bush in a container on a balcony? It would get about 6 hours or a bit more of sun.
Yes, you can, although it is not ideally suited for container growing due to its vigor and type of growth. You will need to be mindful that the roots don’t freeze in winter and that you keep the container away from strong, cold winds. The key will be selecting a large container (at least 5 gallon or 60cm/24 inches in diameter and 50cm/20 inches deep) with plenty of drainage holes. Keep in mind that large containers are hard to move around. If you plan to move the pot around a lot, consider positioning the container on a base with wheels. The red elderberry prefers a sunny position and at least 6 hours of sun per day should be enough.
Grow the elderberry in good soil rich in organic matter. You should ensure that it is well watered and does not dry out. However, in pots and containers, excess water will make roots rot rather easily, hence the need for good drainage. During the summer, low doses of liquid fertilizer can be used weekly.
Elderberry canes need to be pruned severely in late winter or early spring after which you can fertilize them with a balanced slow release type of fertilizer and add some compost. Remove any diseased, damaged, dead, or drooping canes by cutting them off at soil level. The canes will produce a light crop in their first year, a heavy crop in their second year, and decline in their third year. Remove all the third year canes and leave a few first and second year canes in the container (5-8 canes depending in the size of the container).
Sources:
http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=278937&isprofile=0&cv=4
https://www.gardeningknowhow.com/edible/fruits/elderberry/elderberries-in-containers.htm
http://www.madaboutberries.com/elderberries/growing-elderberries-in-pots-and-containers.html
March 2020
- What vines would you recommend for a large pot with an east-facing exposure?
This is such an interesting question because many vines do best in full sun, as demonstrated by their proclivity to climb to the tops of trees! An east-facing aspect means early light as the cool air temperature increases from an overnight low. In this setting we are looking for vining specimens that thrive out of the midday heat of full sun, in cooler air and partial shade.
Additionally, it is important to differentiate the growth habits of a plant confined to a pot, and one that is planted in the ground. Unless quite large, a pot is a limited environment better suited to annuals. The soil requires annual refreshment, as well as more frequent irrigation throughout the summer months. Overtime, large vines in pots might lack needed nutrients and moisture, become root bound, and experience stunted growth.
If your east-facing planting is truly limited to a pot, you may consider annuals (or semi-annuals) such as:
· sweet peas or shell peas
· passion flowers
· jasmine
· hops
If you are able to plant vines directly into the soil in an east-facing exposure, or in a really big pot, you could enjoy larger, perennial vines such as:
· climbing honeysuckles
· climbing hydrangea
· hardy kiwi
· star jasmine
· evergreen clematis
Whatever you end up planting, be sure to keep it well fed with regular (2x per year) mulching of rich compost, and adequate irrigation to see it through our summer drought.
Source: C. Bricknell. (2016). RHS A-Z Encyclopedia of Garden Plants. New Haven, UK: Denton Island Books.
- How do you prune grapes to train it to a horizontal structure?
There are various methods to establish specific grape vine structures based on considerations such as site condition, grape varieties and uses, etc. All rely on basic pruning methods that consider the growth habit of the vines.
Grape vines are long-lived, so after planting, it is important to focus on creating a plant structure that will best support continuous fruiting. This process will take two or three years, during which you should not be concerned with fruit production. Just like a fruit tree, fruiting vines need to be trained while they are becoming established. By properly training a vine’s growth habit, the gardener can avoid rampant growth and the poor fruit production that follows.
Grapes grow on new wood arising from last year’s wood. Therefore, once grapes are harvested, the stem from whence they grew is cut back to the permanent stem (also known as a rod). The rod is the grape vine that you have trained, the one you see in summer and winter, the one that grows thick and gnarled. This is the vine structure that you will train along your horizontal structure, be it wire or wood.
It is crucial to prune at the coldest time of the year. When you prune back the year’s fruiting vine, leave two buds of this year’s vine, rather than cutting back to the rod. When you prune, do so a bit away from the outermost bud that you are leaving. This will leave fruiting spurs for the next season’s growth. When rods become overly gnarled and congested, use a pruning saw and good judgement.
Source:
C. Brickell & D. Joyce. (2003). Pruning and Training. London, UK: Penguin Random House.
February 2020
- My pear tree leaves have orange spots on them. What could be causing this and how do I control it?
The bright orange, irregular spots appear on pear leaves in early summer. This is a fungus called pear trellis rust (gymnosporangiumfuscum). All pears and junipers are susceptible as the disease occurs mostly in South Coastal B.C. and Washington. Symptoms on junipers are swollen orange masses of spores in early spring on stems. The spores from the juniper affect pear leaves and vice versa. Pear leaves are newly infected in spring and twigs may become infected so that the pathogen remains through winter in the trees.
The level of infection on pears may vary from year to year depending on amounts of spring rain and wind direction patterns which spread the fungus spores from junipers. Lightly infected pears may look unattractive while a heavier infestation can cause poor fruiting and tree growth. Junipers in the area may look fine. It is the proximity of the two species growing which causes the spread of the pear trellis rust. Pears and junipers should be growing no closer than 30 meters, or 100 feet from each other.
To control the fungus have a look around your neighbourhood for junipers growing nearby. Have your neighbours look around their yards for susceptible junipers. Replace the junipers with ornamentals or resistant juniper species such as juniperis horizontalis, j. communis or j. squamata.
To prevent the disease from spreading to pears, remove infected junipers before April 1 and dispose of the brush, but do not compost.
To prevent the spores from moving back from pears to junipers in late summer, pick off all infected pear leaves by mid August. These leaves you can compost as the fungus on them dies quickly.
Do not use fungicides on the pear or juniper trees. Instead, look for swollen growths on pear twigs. This indicates the infection has entered the tree. Prune these out during the winter and dispose of the pruned wood.
Source:
West Coast Gardening Natural Insect, Weed and Diseas Control by Linda A. Gilkeson, PhD, 2013.
- My Clematis armandii has turned black. Why and what can I do about this?
It is worth keeping weather notes as a gardener. Weather patterns are less predicable than they were in the past, with more drought and occasional very cold periods. Normally plants’ natural dormancy in winter protect them from cold, but it depends how quickly temperatures fall and for how long. Cold injury can show up weeks later, with plants showing blackened tips or they may even be killed to the ground. Roots may still survive and the plant regrow when temperature warms in spring. Having well drained soil which is insulated with mulch in the fall helps protect plants over the winter and early spring.
A year ago our area was hit with an unusually long very cold period which caused injury to many gardens. Plant disorders are more frequent with unusual weather and can cause plants to subsequently suffer from disease.
Another possible cause of the clematis blackening is the fungus asochyta cleamatidina, or clematis wilt. Foliage and stems may dry and wither, sometimes turning black. Reddish lesions on the stems can sometimes occur and the plants may decline very rapidly after initial damage is spotted. The fungus spores spread on remaining vines or are carried by wind from a nearby clematis. Damp and humid weather increases the risk of infection. The vascular system of the plant is cut off by the spores in a process where water can’t be carried by the plant. Other funguses can cause clematis wilt as well.
Treatment for this condition is to prune out the infected stems to the ground at the first sign of withering. Provide good air circulation with the plant by pruning some stems away in the growing season if the plant surpasses its growing space and becomes overly thick. Sterilize the pruning blades with a weak bleach solution as you cut. Cut all stems to the ground in the fall and dispose of all the foliage rather than composting to prevent reinfection. Ensure good growing conditions: site the plant with shade over the roots or put a stone over the area (not touching the stems), plant deep, water adequately, mulch in spring and winter, and provide support so stems are not weakened and open to disease.
Sources: https://www.rhs.org.uk/advice/profile?PID=125
https://davesgarden.com/community/forums/t/896870/#b
https://www.thespruce.com/how-to-deal-with-clematis-wilt-1402785
West Coast Gardening Natural Insect, Weed and Disease Control by Linda A. Gilkeson, PhD, 2013.
Jan 2020
- What are some evergreen hedge options?
First off, remember to choose a plant that is right for the right location. Things to take into consideration include: the ideal plant conditions such as light, soil, exposure, zone, water requirements; the purpose for the hedge; where will the hedge be placed (i.e., area of the garden; property line designation; privacy); how will the hedge fit with the overall style of the garden; maintenance requirements for the hedge; and height preference (i.e., visibility restrictions). There are some other considerations when planting a hedge. Do not plant a fast growing hedge unless you are prepared to maintain them and keep under control. Columnar shapes lend themselves more for hedging because of their narrow form and less width. Smaller leaved forms are better suited for the perfect clipped hedge.
Recommended varieties of varying heights include:
Abelia grandiflora (Great Plant Pick) – also deer resistant
Bamboo
Berberis julianae (Great Plant Pick) – also deer resistant
Buxus spp.
Camellia japonica
Chamaecyparis lawsoniana varieties
Cotoneaster simonsii
Cupressus ‘Swan’s Gold’ – columnar
Escallonia varieties
Euonymus japonica varieties
Ilex crenata ‘Northern Beauty’ (Great Plant Pick)
Juniperus chinensis ‘Hetzii Columnaris’
Juniperus sopulorum ‘Grey Gleam’
Junipeerus virginiana ‘Skyrocket’
Lonicera nitida
Lonicera tatarica (pink and fragrant).
Ligurstrum japonica varieties
Nandina
Osmanthus delavayi
Pittosporum Tenuifolium (check zones – some tender)
Taxus – slow growing
Tsuga canadensis varieties
Thuja occidentalis ‘Smaragd’ (Great Plant Pick)
Thuja occidentalis other varieties
Sarcococca confusa (Great Plant Pick) – also deer resistant
Viburnum tinus
Sources:
https://research.wsulibs.wsu.edu/xmlui/bitstream/handle/2376/5283/EM089E.pdf?sequence=2
N. Ferguson (1984). Right Plant, right place.
R. Lancaster (2002). Perfect Plant, perfect place. DK Publishing, Inc.
- Do you need a male and female holly plant to produce berries?
Yes. Hollys (Ilex augustifolium) are dioecious, meaning that they need male and female plants in order for pollination to occur for berry production. So only female holly bushes will have the red berries. This means that if some holly bushes do not have berries, they may be male and simply cannot produce berries.
With evergreen holly, you will generally need 1 male for every 20 female hollies. These hollies can be up to 500 feet apart – although 300 to 400 feet is typically recommended.
Winterberry (deciduous) holly needs to be closer than evergreen holly. You’ll want to plant 1 male for every 5 to 10 female. Plant the male holly within 50 feet of the female holly.
If you have a holly bush with berries in your garden and no holly plant nearby, you may have a situation where both a male and female were planted at time of purchase in the same container.
Source:https://www.rhs.org.uk/plants/9087/Ilex-aquifolium/Details
- When should a curly willow be pruned?
The corkscrew willow, Salix matsudana 'Tortuosa', is also known as the Hankow willow, curly willow, dragon's claw, or globe willow. Prune the corkscrew willow only during its dormancy period, just after it completes its fall defoliation in the winter or, at the latest, early spring. This is because willow trees, like most trees, bleed sap if they are pruned during their active growth period. Remove diseased and ailing branches with sharp, clean secateurs. To prevent passing the infection throughout the plant, sterilize the pruners if removing diseased branches and between cuts.
Source:
https://www.rhs.org.uk/plants/82656/Salix-babylonica-var-pekinensis-Tortuosa-(f)/Details
https://www.rhs.org.uk/advice/profile?PID=954
Dec 2019
Ornamental
- I want to move a rhododendron. Can you tell me if and when I should do this?
Yes you can move rhododendrons. Rhododendrons have relatively small rootballs making it easy to move. In our climate (Pacific Northwest ) you can move them anytime of the year however spring is First choice and fall is second choice.
Reference: Rhododendron.org
Edibles:
- How do you prevent powdery mildew on peas?
Keep your plants healthy with well drained soil and good air circulation. Keep your garden clean of leaf debris in the fall as the powdery mildew can overwinter. Consider planting disease resistant varieties in sunny locations.
You can try spraying various solutions as a preventative and control if you see any evidence the powdery mildew. Solutions of: horticultural oil (neem) or, 40-60 parts milk to water, or a bacterial spray of Bacillus subtilis, sprayed on your plants before they become infected repeating as directed by label on package generally 10 to 14 days.. Mxed reports of homemade 1% baking soda to water.
It was thought that ground watering in the early morning allowed the pants to dry b4 the heat if the day. Now, spraying the leaves with water a few times a week during the day can inhibit the spores as they prefer high humidity rather than wet.
Reference: Saferbrand.com , Linda Gilkenson book natural insect, weed and disease control
Nov 2019
- When do I prune forsythia and hydrangea?
These shrubs are pruned at different times of year. The forsythia blooms in early spring on the wood produced the previous year. So leave the pruning of this shrub to right after flowering. By doing this promptly the shrub has the maximum amount of time of development of growth for next year’s flowers before the end of summer. Leave renovation pruning to after flowering also.
Mop head and lace cap hydrangeas won’t need a lot of pruning but doing so regularly encourages new vigorous growth that will provide a better flower display. Do this in late winter, very early spring. Deadheading the old flowers is best left to spring as severe weather, as we experienced in Feb. of this year, can damage underlying growth buds if the old flowers are removed.
Hydrangea paniculata and hydrangea arborescens should be left until spring so that a framework can be developed around a few new buds.
Renovation pruning can be done in late winter.
Sources:
https://www.rhs.org.uk/advice/profile?PID=197
http://ccenassau.org/resources/-hydrangea-types-and-how-to-prune
- My cucumber and zucchini plants did not do well last season. Are there varieties that are self pollinating?
These plants have separate male and female flowers on the same plant and depend on bees or people to carry pollen from the male to the female flowers. In a small garden bees may not notice the flowers or weather may be cool. Bees are scarcer now and they also are less active when it is cool and wet.
Hand pollination is easy for gardeners to do: when the male flower has pollen on it transfer some to the open female flower on the one day that it is open using a small brush.
There are varieties of plants which set fruit whether or not the flowers were pollinated; these are called parthenocarpic. These varieties are gown in greenhouses or poly tunnels to avoid pollination as this can cause fruit to become misshapen and bitter.
As an example, West Coast Seeds carries the following parthenocarpic cucumber seeds: Roxynante, Socrates, Tyria, and Ishtar.
Varieties of parthenocarpic zucchini include Partenon, Noche and Dunge.
Sources:
Gilkeson, L. (2011). Backyard Bounty, The Complete Guide to Year-Round Organic Gardening in the Pacific Northwest. New Society Publishers.
Gilkeson, L. 2013. West Coast Gardening Natural Insect, Weed, and Disease Control.
West Coast Seeds Gardening Guide 2019.
October 2019
- Do I fertilize before or after planting a new lawn?
Prior to establishing your new lawn, you can get your soil tested for phosphorus, potassium, calcium, magnesium, organic matter, and pH. If needed, you can apply phosphate and lime by working them directly into the soil. Nitrogen and potassium are water-soluble, and can be added after seeding or laying sod.
If you don’t plan on testing your soil, you can simply apply a good 10-20-20 fertilizer prior to seeding or laying sod, incorporating it to a depth of two or three inches. This way everything the growing grass requires is immediately available for the first four to six weeks.
Once established, regular fertilization is important to maintain a healthy lawn. If you tested your soil, and have adequate levels of phosphorus and potassium, you need only apply nitrogen regularly. Nitrogen should be applied four times per year (May, June, September, and November), four pounds per 1000 square feet. Phosphorus and potassium leach slowly from the soil, so if these are needed, apply one to two pounds per 1000 square feet, once per year. Lime is also required to provide calcium and magnesium, and in our climate should be applied in the fall or early spring, 25-50 pounds per 1000 square feet.
Other more organic methods of feeding a lawn include using bone meal for phosphorus, leaving grass cuttings on the lawn to provide nitrogen, and topdressing with a fine compost.
Resources:
Sustainable Gardening: WA/OR Master Gardener Handbook (2008)
California Master Gardener Handbook, 2nd Ed. (University of California, 2015)
Encyclopedia of Gardening Techniques (American Horticultural Society, 2013)
- Is Jerusalem Artichoke invasive? Can I plant it in a pot?
Helianthus tuberosus are a kind of sunflower, and are neither from Jerusalem nor are they artichokes. They are better known as sunchokes. Sunchokes propagate by hardy, perennial tubers that spread underground. These tubers are the edible product - an easy source of low calorie carbohydrates – while the above ground plants can grow into dense stands, six to 10 feet in sun. The tubers don’t store well, so are best left underground to overwinter, and dug up prior to consumption.
Because of the spreading habit, and because any tiny piece of tuber can regrow, sunchokes can be considered invasive if unwanted, or if planted in the wrong place. They are nearly impossible to eradicate once established. Therefore, it is recommended that careful consideration be given prior to establishing a patch. They should be given an area with room to spread, not in competition with other fruit or vegetables, in full sun with well-drained soil.
Sunchokes can be planted in large pots, as long as the soil is amended with organic matter regularly, and not left to dry out. An alternative is to use a root barrier in the garden to surround the plants, dug down two feet into the soil. Uncooked tubers should be kept out of compost to avoid accidental redistribution.
Resources:
Backyard Bounty (Gilkeson, 2018)
The Zero-Mile Diet (Harriot, 2010)
September 2019
- What can I plant under a garry oak tree?
Garry oak (Quercus garryana) are a very special part of our local landscape (southeastern Vancouver Island and the Gulf Islands and lower Fraser Valley) as they grow nowhere else in Canada and are the only native oak in BC. Less than 5% of the Garry oak ecosystems remain in a near-natural state and this has put many plants (including the Garry Oak) and animals at risk. For these reasons, you may want to consider creating or restoring the Garry oak habitat by planting a native garden. If non-native plants such as Scotch broom, daphne, and some grasses have invaded the area around your Garry oak tree(s), you may wish to remove them and re-establish wildflowers and other native understory vegetation. Depending on the size of the area you have available, this may seem like a daunting task. However, GOOD NEWS - there are resources available from the Garry Oak Ecosystems Recovery Team Society (GOERT; see below) to guide you through this process!
Understories for Garry oak may include meadows plantings where there is ample open space or woodlands plants where the soil is deeper, richer and moister. Garry oak meadow species include Plectritis (sea blush), generally the first to flower in February. Dodecatheon (shooting stars) and Erythronium (fawn lily) then emerge and Camassia (camas), Fritillaria (chocolate lily), Trillium, Allium (onion), and Triteleia (triplet lilies) are some of the other flowers to follow. Many of these bulbs also grow in woodland areas as do shrubs such as Holodiscus discolor (Oceanspray), Mahonia aquifolium (Tall Oregon Grape) and Rosa gymnocarpa (Baldhip rose). Sometimes Garry oak are found on shallow soil sites that can not be easily developed. Even in these sites native flowers, grasses and mosses can be established as ground cover.
Resources:
http://www.goert.ca/documents/GOERT_Gardeners_Handbook.pdf
https://metchosin.civicweb.net/document/1751
https://botanicalgarden.ubc.ca/visit/garden-highlights/garry-oak-meadow-and-woodland-garden/
- I am getting tiny holes and cut outs on my kale leaves. What’s doing this?
There are a variety of pests that can attack kale but based on this description the most likely culprit is the cabbage worm. Actually there are several insects that cause this type of damage and are often generally referred to as ‘cabbage worms’. These include the imported cabbage worm, the diamondback caterpillar and the cabbage looper. The cabbage worm will eventually become a butterfly, whereas the diamondback caterpillar and the cabbage looper will become moths. The adults come and lay their eggs on the leaves of your kale and the eggs quickly hatch and the young caterpillars start feeding. They are usually more prevalent in late summer and fall.
In order to naturally deal with these pests you can spray your kale with strong jets of water from a garden hose to physically remove any that are on the leaves. Use a row cover barrier to prevent egg laying. Another option is to hand pick pests such as caterpillars off of your kale leaves as needed. Spraying leaves with BT (Bacillus thuringiensis) will work and is an organic solution. Try planting resistant varieties such as red-coloured leafy greens, which the cabbage worm tend to avoid. Introduce natural predators of the cabbage worm such as larvae of parasitic wasps. Plant your leafy greens in spring rather than in late summer/fall when the cabbage worm is not as active.
Resources
http://www.birdsandblooms.com/blog/got-holes-in-your-leafy-greens-you-have-cabbage-worms/
hhatttps://www.growveg.com/guides/3-common-kale-pests-and-how-to-manage-them/
https://www.almanac.com/pest/cabbage-worms
August 2019
- What do I need to do to care for my Nandina Domestica?
Nandina Domestica also called Heavenly Bamboo is an easy to care for evergreen shrub. With many varieties available that typically grow 4-8’ tall and 2-4’ wide. While it will survive in many situations of soil and light exposure within zones 8-10, for it to thrive and look its best consider the following.
Plant in full sun with some afternoon shade in rich, consistently moist yet well drained hummus(y) soil. Once established they do have some drought tolerance. They can benefit from once a year (spring or fall) light fertilizing with a for acid-loving plant food. Having a single plant may not be very dramatic so grow a bunch for the best showing. Note that in some areas in the southern USA it is considered invasive by both growing through underground rhizomes but also by the berries being carried away by birds. Regarding the berries, they are toxic to people, livestock, and pets as well as birds. Most notably the Cedar Wax Wing has been known to gorge on the berries (in the areas where it has become invasive) and have died. Here in Victoria, the Cedar Wax Wing has a large choice of fruiting plants and it is believed that is why we haven’t seen problems with them. But, for some they might cut the berries off just enjoying the plant. Alternatively there are non-fruiting varieties where you can still enjoy the leaf colour.
Sources:
https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=c772
https://homeguides.sfgate.com/fertilize-nandinas-74126.html
- I would like to grow vaccinium parvifolium in my veggie garden. How do I plant this and care for it?
For a healthy, producing plant, it is all about getting the placement right. Depending on the lay of the land, Red Huckleberry might do well in your shade or woodland garden. However, a veggie garden has much more light requirements than the huckleberry can tolerate. Its native habitat is partial to full shade with rich hummus, extremely well-draining acidic soil. They grow on nurse logs, which allows the winter rains to flow over the roots.
If you have an area like this in your garden Red Huckleberry is best grown from seed or by layering. Transplanting may result in high mortality. You can order from your local nursery or specialty native nursery. Alternatively, you can pick ripe fruit and use the seeds by following these guidelines:
Collect fruit when berries are ripe in July through August (they should be bright red). Following collection, chill the fruit to 10 degrees C for several days. Clean the seeds by macerating and floating off the pulp and unsound seed. Clean the seeds carefully. Since they are miniscule, so you may want to use cheesecloth to strain the seed from the pulp. Seeds dried at 15-21 degrees C for two days can be stored in a refrigerator for up to 12 years. Fresh seed not planted in the fall may germinate better if cold stratified for 1-3 months. Stored seed germinates well when exposed to alternating temperature and light regimes of 28 degrees C for 14 hours of day (light) and at 13 degrees C for 10 hours of dark. Fresh or stored and cold-stratified seeds can be sown directly into flats or small pots (a salt shaker can be used for sowing). Plant in a mixture of sand and peat moss. Seedlings will begin to emerge in a month and will continue to emerge for quite some time thereafter. Transplant seedlings into larger pots 6-7 weeks after emergence. Plant outside after the first growing season. Water as needed. Seeds are very slow to sprout and seedlings are small and grow very slowly. The establishment phase of this endeavor is critical—the transplant must receive the proper amount of moisture; too much or too little will lead to certain death!
While not for the faint of heart and assuming you can find the right spot away from your sun loving vegetable garden, you could have a wonderful berry supply for years to come.
Sources:
https://plants.usda.gov/plantguide/pdf/cs_vapa.pdf
http://nativeplantspnw.com/red-huckleberry-vaccinium-parvifolium/
June 2019
- I need to move my hellebores. How and when do I do this?
Hellebores should only be moved when necessary, but if you are already moving the Hellebore anyway it is an optimal time to also divide it. Hellebores are best transplanted and/or divided in September or October. Hellebores initiate a burst of root growth in autumn and so the best time to divide them is immediately prior to this spurt of root development. This allows the growth of new roots to settle in the newly divided plants at once.
If you wish to divide the hellebores when moving them you should dig up the whole plant by digging an 8-inch-deep circle around the hellebore plant, 6 inches from its outermost leaves. Once loose lift the plant from the ground and wash the crown free of soil so you can see what you are doing and then cut between the growth buds with a sharp knife. If you leave at least three buds in each division the plant will recover more quickly. Each new division must have a minimum of one bud (preferably 2-3 growth buds), some woody rhizome tissue, and some growing roots. Each little transplant should then be planted with plenty of organic matter in a partially shaded location and watered thoroughly.
When you’re done, mulch around the transplants with a layer of leaf mulch or compost and continue to water regularly until established.
Sources
Hellebore Care Instructions https://northwestgardennursery.com/our-hellebores/culture/
Transplanting a Hellebore https://www.gardeningknowhow.com/ornamental/flowers/hellebore/dividing-hellebore-plants.htm
How to Divide Helleborus https://www.gardenguides.com/12460286-how-to-divide-helleborus.html
- What is eating the leaves of my trees and shrubs? What can I do about this?
The most likely culprit is likely to be winter moth (Operophtera brumata) caterpillars. They hatch in spring and appear as smooth, green “inchworms” up to 2 cm (3/4 in) when fully grown. These little caterpillars can decimate the leaves of a tree at this time of year leaving them thoroughly chewed and lacey-looking. Fortunately, because trees are vigorously growing in the spring, they usually re-foliate.
The adult females are unable to fly so have to climb the tree from where they emerged on the ground between October and January to mate and lay their eggs. To prevent the females climbing and ultimately laying eggs, sticky control bands can be put around the trunks after mid-Oct, taking them down in February. Dormant oil spraying between December and February before the leaf buds swell will also kill eggs. Spring spray of BTK when caterpillars are small and actively feeding can also kill the caterpillars, but unfortunately may kill other caterpillars as well.
Meanwhile, this summer, ground beetles are a major predator of the cocoons, killing lots of winter moth while they are pupating. So gardens that harbour and protect ground beetles (i.e., NO sprays, leaving soil undisturbed/minimum cultivation) will have better control of this moth.
Source:
Gilkeson, L. Natural Insect, Weed & Disease Control.
- What are to small notches on the margins of my pea plant leaves and should I be concerned?
These are likely the results of adult pea leaf weevil, which is a fairly serious pest for agriculture. This tiny grey insect feeds exclusively on leaves as an adult, chewing a tell-tale halfmoon notch along the margins of the leaves. But the real damage is done by the larval stage when the tiny white grubs feed on the roots of the nitrogen fixing nodules of the roots. They also feed on other legumes including broad beans, vetch and clover as adults but only peas and fava are used by larvae.
Adult weevils overwinter in debris and become active in March. Through April and May, they feed on leaves and lay eggs in the soil near the pea plants. Larvae feed on the root nodules until June, pupate and emerge as adults in July to feed on the leaves until August.
Large numbers of weevils can have serious impacts on legume production. The best approach appears to be to plant peas late in the season – in late May and June – to avoid peak adult weevil feeding and egg-laying. In future years, it might be worth growing from seed indoors and giving the plants 2-3 weeks of growth before putting them in the soil. If you think your plant has been attacked by weevil larvae, a dose of nitrogen rich fertilizer may help to make up for losses associated with lost nitrogen fixing nodules.
It is good practice to get rid of all affected plants, roots and all, to destroy larvae and if you use cover crops, stop using vetch and clover. Crop rotation is also an excellent practice.
Pea leaf weevil is not to be confused with pea weevil which lays its eggs in the developing pea pod and larvae consume the peas inside.
Sources:
Gilkenson.ca April 29, 2014: Warm Weather & Pea Leaf Weevils, www.msuextension.org/pspp/documents/PeaLeafWeevil.pdf
May 2019
- Which clematis is evergreen that can cover a large area?
Answer:
There are many varieties of Clematis but the one you are looking for is Clematis armandii.
This is a timely question as I just purchased two (yes, two) such vines. I couldnít resist the evergreen vine with pretty white flowers emitting a heavenly scent! What more could you want?
Clematis armandii, also known as Armand clematis is named for Pere Armand David (1826-1900), a French missionary and botanist who traveled throughout China collecting specimens in 1885 for botanical identification. It took some time (1900) before it was collected for propagation and finally arrived in North America in 1934.
Varieties / flowers
There are a few varieties available, with the easiest to find being Snowflake producing white blossoms, then Apple Blossom, with a light pink flower, and 'Hendersonii Rubra,' with deep pinks backing white flowers. The flowers are 5-6.5 cm (2-3 in) long, 4-7 sepals (star shaped showy parts) in large branched clusters. They have a sweet fragrance of vanilla or notably honey and almond, giving you reason to have them within reach of foot traffic such as gate arbours. It's also popular with bees, blooming in late winter or early spring for about a month around the same time as Forsythia. Coiled plumed seed heads follow the flowers in late spring and are considered attractive.
Leaves & Stems
Clematis armandii is a vigorous growing broadleaf evergreen vine, reaching lengths of 6-7.5m (20 - 25 ft.) or longer and can spread to 3m (10ft). The leaves emerge with a bronze tone then green up to a glossy dark green and grow opposite to each other. They are pinnate compound, with 3 leaflets, 7.5-15 cm (3-6 in) oblong-lanceolate to ovate, pointed, margin entire and droop downward. These drooping leaves are graceful looking over a fence or arbor creating a soft weeping appearance.
The stems are twining with tendrils that allow it to grab structures and other plants, then drop down and flounce gracefully, rather than reach for the stars like other vines. For those reasons, the vine is perfect for softening the top of fences or shrouding an archway. Just give it plenty of support with a strong arbor or trellis because with time the vine can become heavy. As it matures, evergreen clematis also becomes quite woody, with all its new growth forming at the top of the plant. Pruning is Group A, meaning that flowers develop on the previous year's growth. Any pruning (if needed) should be done after flowering to avoid build-up of tangled dead stems in the inner parts of the vine yet not affect the next season flower bud development.
Cultivation
Clematis armandi can be propagated by softwood cuttings, taken in early summer. Provide a site with humus-rich well-drained soil, a pH of 6-7.5 is recommended by some whereas others advocate an alkaline soil. Plant in full sun along coastal areas and in partial shade in warmer zones. They like their face in the sun and feet in the shade. Cover base with decorative rocks, shells, or mosses. Once established it can be occasionally watered during dry weather. Plant vines that are well rooted and at least two years old about 30cm (12in) away from the wall, fence, or trellis. Ensure the crown of the root is not covered when planting to be sure, plant at the same height that it was in the nursery container. Clematis are heavy feeders and appreciate fertilizing in spring (10-10-10). Provide shelter from drying winds or temperature extremes. In summer, there may be a bit of leaf loss. It is hardy in zones 7 - 9 and won't resist temperatures lower than 14 degrees F (-10 degreesC). Consider extra winter protection like mulching and burlap (if possible). It is not recommended for growing in patio containers. However, extra precautions in winter and repotting every 3-5 years is fine.
Pests & Diseases
Scale, powdery mildew, rust, wilt and fungal spots may be problems.† Sometimes parts of the vine will turn brown and die for no apparent reason. And like other clematis, it can be struck by a disease known as Clematis wilt.† If spotted, remove the stem and destroy (not in compost).†Consider applying a systemic fungicide. Excellent drainage and a sunny enough location will alleviate many of these problems.
Sources:
https://www.sfgate.com/homeandgarden/pickoftheweek/article/Clematis-arma...
https://www.gardeningknowhow.com/.../vines/clematis/growing-evergreen-cl.....
https://www.rhs.org.uk/advice/profile?pid=966
https://www2.viu.ca/milnergardens/Clematisarmandii.asp
https://www.greatplantpicks.org/plantlists/view/383†
https://landscapeplants.oregonstate.edu/plants/clematis-armandii
- Last year I had aphids on my beans! What do I do if they come back this year?
Beans†(any kind) are one of my favorite vegetables, aphids are nearly my least favorites of insects (evil weevils are the worst).
Aphids are a sap sucking insect that feed in colonies. They have fairly complicated life cycles with stem females constantly producing adult aphids without mating and laying eggs until the fall where they lay male and female who then mate and lay eggs that will hatch in the spring. Given this, infestations can occur overnight. Bean aphids vary in color from†green to black. Many aphids are not fussy about the plant they attack but some are very host specific. They will suck the fluids from leaves and flowers of plants. Some aphids have wings allowing them to move about on the plant or to a different plant. Aphid flights are most common during periods of moderate temperatures (60 to 80degrees F). Monitor plants particularly closely during April and May.
The important thing is that they have a proboscis which acts like a straw to suck up your plant's precious fluids. The good news is you can often get effective control by washing aphids with a strong stream of water. When you do that while they are feeding on your plants, the proboscis breaks and they can no longer feed hence they starve. Squishing them is very satisfying as well but depending on how many plants you have it can just be onerous not to mention gross! Please avoid chemical sprays to kill them because you will also be killing the beneficial insects that like eat the aphids and other nasties. Note that ants will farm them and potentially kill beneficial insects to protect their crop!
A favorite of aphids are plants stressed from not enough water. Also, aphid populations tend to be higher in crops that are fertilized liberally with nitrogen. Soil building is the single-most important thing you can do for your garden. Compost keeps your soil aerated, has great water holding capacity, feeds slowly, just perfectly! Good soils keeps plants healthy. Healthy plants are less likely to be infested.
Destroying weed hosts late in the year may also help destroy overwintering populations.†Keeping your garden tidy and your plants healthy and in good airy sufficiently watered environments should be a good preventative. Monitor the proportion of aphid mummies relative to unparasitized aphids and the numbers of predators such as lady beetles. If the proportion of mummies is increasing, or predators appear to be gaining control, and aphid populations are not yet damaging. Based on what you can see you can act accordingly. Mostly keep it simple for a healthy edible food for you not the pests.
Sources:
https://ento.psu.edu/extension/factsheets/beans-insect-identification
https://www.rhs.org.uk/advice/profile?pid=797
https://pnwhandbooks.org/insect/vegetable/vegetable-pests/hosts-pests/be...
Gilkenson, L. (2013). Natural insect, weed & disease control.
What is this plant?
September 2018
January Clinic Questions:
I would like to grow an indoor herb garden. What kinds of herbs can I grow indoors? What kinds of conditions do herbs need?
An indoor herb garden is a great way to keep your hand in gardening all year and provide you with fresh herbs at home for a fraction of the cost of buying them at the grocery store. This is a great gardening alternative for apartment or condo dwellers too. An indoor herb garden takes no more time and effort than any houseplant. With just a little planning, you can grow a luscious array of tasty treats to be added to soups and salads, and used as garnish.
The first thing to consider is the lighting available in your home. Most herbs need as much light as they can get to grow successfully. A sunny spot that that gets four to eight hours of sunlight is sufficient. Windows that face south, southwest, east or west are best though south facing windows may be too hot in the summer and require some shade. North facing windows do not get enough light for growing herbs. As the light quality drops quickly away from the window, you’ll want to place the plants fairly close to the light source. Remember to rotate your plants toward the light so all sides flourish and the plant does not lean to one side. If you do not have a window with sufficient light, you can use fluorescent grow lights, placing them just above the plants (four to six inches) and leaving the lights on for about eight hours. Full spectrum grow lights come in different sizes and prices vary.
Herbs are like people in that they prefer indoor temperatures between 18-21 degrees C. (or 65-70 degrees F.). At night, the temperature close to a window may drop to 12 C. (or 55 F.) but most herbs don’t mind as long as the leaves don’t touch the window glass (brrrr). Some herbs, like basil, do not like the cold and prefer to be warm throughout the day (about 21 C. or 70 F.). Keep your herb garden away from the drafts caused by open windows or doors.
Now, how to choose the herbs for your indoor garden. This will partially depend on your taste (literally!) and the type of lighting available. There are many herbs, leafy greens, lettuces, edible flowers and some peppers that will thrive indoors. Some plants that love and need a VERY sunny location are: thyme, oregano, sage, marjoram, chili peppers, basil, parsley, cress and calendula. Others prefer a slightly shadier spot: mint, chives, lettuce, spinach, parsley, thyme, mizuna, and miner’s lettuce. You might want to start with just two or three of your favorites (e.g. oregano, chives and mint or rosemary and thyme). If planting many different types of herbs together, you’ll want to choose ones that like similar conditions (e.g. Mediterranean herbs such as oregano, marjoram, thyme particularly love sun and good drainage; lettuces grow well together). Some herbs, like the mints, tend to take over an area and should be grown in a pot by themselves. Mint may require frequent repotting. Rosemary, bay, and sage can be left in a container for several years before repotting.
Next, you will need to select containers for your herbs. While any pot at least six inches deep will do, glazed or plastic pots do not dry out as quickly as other types of pots. The deeper the pots, the more room there is for root growth. Window boxes are ideal. Make sure the container has drainage holes and set the pot on a saucer, liner or drain pan. You can even set the pot on some pebbles in the saucer. This serves two purposes: first, it provides humidity for the herbs that may be warranted in dry indoor air, and second, it reduces the likelihood that the pot (and roots of the herbs) will be sitting in water. Herbs don’t like to get their feet wet!
You will want to use a good quality potting mix in which to grow your herbs. The nutrients in the soil will feed the plants and fertilizing will be kept to a minimum. Herbs do not require much feeding from fertilizers in the winter but occasional feeding (once per month) with a food-safe natural product may be warranted in the growing season. If you want to grow your herbs from seed, you can plant the seeds in some starter mix (lighter and airier that potting soil) in smaller containers like peat pots and transplant them into your larger herb containers when they have at least two sets of true leaves (about eight centimeters tall). Or you can purchase starter plants or seedlings from nurseries or garden centres. These are usually available from late spring until the fall. Put some soil in the bottom of your container, place the plant gently on top of the soil and fill with potting mix, pressing the soil firmly around the plant. Make sure the crown (where the roots meet the stem) is level with the top of the soil (i.e. not buried). Leave some room at the top of the pot (about one inch) to allow for watering. Try putting three plants in a window box, leaving some space between them so they have room to grow. While you’ll want to keep your herbs watered regularly, they don’t want too much water and never want to stand in it. Too much water will cause them to wilt and lose their flavour. Check them daily and water when the top of the soil feels dry. Never let them dry out completely. Remember that different plants may have different watering schedules and this may change with the seasons.
Herbs are not bothered much by pests but if you see some bugs chewing on the leaves, mix up a mild solution of soapy water and spray well.
In very little time, you will have herbs growing, though they may appear more stretched out and spindly than those grown outside and will not be quite as productive. You can still harvest the leaves regularly but never remove more than one third of the plant. This might even encourage the plant to become more compact. If you are aiming for edible flowers (e.g., violas, calendula, pansies), be sure not to remove the flower buds. You can harvest fresh herbs by pinching back the tips of the stems to eat them fresh or cut the stems and air-dry them in bunches. You can move your containers outside in the summer and bring them in again before the first frost in the fall. Remember to check for pests when you bring them in. Better yet, keep your herb garden indoors all year. Happy herbing!
Sources:
The Herb Gardener: http://theherbgardener.blogspot.ca/2008/06/tips-for-growing-herbs-indoors.html
Canadian Gardening: http://www.canadiangardening.com/gardens/indoor-gardening/how-to-grow-windowsill-edibles/a/29994/2
Royal Horticultural Society: https://www.rhs.org.uk/advice/profile?pid=142
Montreal Botantic Garden: http://espacepourlavie.ca/en/growing-herbs-indoors
Growing Herbs by Y. Rees & R. Titterington, Whitecaps books, 1994.
What should I be doing in my garden during the winter months (Nov. – Feb.)? What can I do to get ready for spring?
Well, what you do in your garden during the winter months really depends on how active you wish to be. For those living near coastal B.C., there are a number of gardening activities that can be pursued throughout the year.
Many edible plants such as vegetables can be planted in the summer for fall and winter harvesting (i.e. winter gardening). These include arugula, broad beans, calendula, chervil, corn salad, lettuces, mescluns, mustards, pac choi, scallions and turnips to name just a few. Other plants can be kept in the ground over winter (i.e. overwintered) for harvesting in the spring and summer. These include certain varieties of garlic, onion, cauliflower and broccoli. They need this extra time to fully develop and do not require protection during the winter. In early spring, they will start to grow quickly and you can harvest them as you are planting your spring crops. You can also plant bulbs like tulips in late fall, if you have not done so already.
Another activity that can be carried out, if you have not already done so, is cleaning up and preparing your garden for spring. In the late fall, there are likely to be fallen leaves and woody debris that can be removed. This is particularly important if you have a pond with fish as the leaf decay releases methane gas into the water which can be fatal to fish. You will also want to cut back herbaceous perennials and pull out annuals or other debris to prevent rot. Many communities pick up kitchen and garden waste or have composting centres. Some communities also have composted materials available for use by area residents – check out your local municipal website. You may also wish to raise your containers onto pot feet (or little blocks of wood) to prevent water-logging.
You can also take this opportunity to prune out diseased, dying or dead branches from shrubs and trees. When no leaves are present, it is easier to see where these areas are and the plants are dormant at this time. You may also wish to remove any odd looking branches or prune to enhance the shape of the shrub or tree.
Another great later fall and winter activity is to enhance your garden soil by applying mulch to your garden. Organic mulches can contain compost (commercial or homemade), composted sawdust, chopped or composted leaves. Two to three inches of mulch can be applied but be careful to avoid the crown (where the stem meets the roots) of perennial plants, just bringing the mulch up to the edge of the crown.
You may also wish to set out slug traps by filling an empty tuna fish or cat food can with beer (even the non-alcoholic variety will attract slugs) placing it in a shady spot with the rim of the can at ground level. Empty the can every few days and refill. Be sure you are not also catching creatures that are beneficial to your garden.
Winter is also a great time to walk through your own garden or local botanical gardens to view the variety of plants with winter interest. Interest in winter may come from flowers, berries, coloured stems or foliage. Hellebores and some varieties of clematis bloom over the winter months. Other plants like mahonia and hamamelis (Witch hazel) bloom over the winter months in bright oranges or yellows. Some varieties of cornus (dogwood) have spectacular winter bark or fruit. Many shrubs like nandina have a lovely display or berries over the winter months. By January, some of the early bulbs like galanthus are beginning to bloom. There is never a dull moment in the coastal garden!
Another way to be working on your garden during the winter months is to check out seed catalogues and lists and make some choice selections for spring planting. While seed catalogues are now available to leaf through (pardon the pun), many plant lists are also available via the internet with easy access to information on each plant with direct links. How easy does that make gardening? Happy winter gardening!
Sources:
Canadian Wildlife Federation: http://cwf-fcf.org/en/resources/gardening/gardening/putting-your-garden-to-bed_resource.html
Royal Horticultural Society: https://www.rhs.org.uk/advice/in-month
West Coast Seeds: https://www.westcoastseeds.com/
Canadian Gardening’s Water Garden by J. Davis, Penguin Studio, 1997.
December Questions
Where is the best place to buy soil?
Before you buy soil by either picking it up yourself or having it delivered, have a good look at what you are buying. Good quality soil is called loam, and is a mix of roughly equal proportions of sand, silt, and clay. It should have good structure and be well drained. All soils benefit from the addition of organic matter such as well rotted compost.
Look out for things such as a high stone content, thick fibrous roots, weeds, and contaminants such as brick or glass. Ask the supplier where it is from and whether it has been tested and what are the results. Check for evidence of invasive plants such as Japanese knotweed, horsetail, couch grass, and weed roots and shoots. Weed roots are often white and fleshy.
Here is a list of local suppliers:
MacNutt Enterprises Tri Landscape Supply Michell Excavating Integrity Sales and Distribution Victoria Landscape Gravel Mart Peninsula Landscape Supply Gardenworks Blenkinsop location
Sources: Washington State University, www.cru.cahe.wsu.edu Royal Horticulture Society, www.rhs.org.uk
When do you take scions for grafting?
Grafting and budding are used as the principle methods of propagating in certain plants such as fruit trees. They are techniques used to combine one plant with another to encourage growth as a unified plant, one that is identical to the parent plant.
Factors affecting successful grafting or budding are: temperature, time of year, age of the plant parts, scion orientation, and care of grafted plants, soil moisture, and contact of stock and scion.
According to Ross Penhallegon, a horticulturist with the Oregon State University Extension service, peach, nectarines, cherry, and prune wood is best collected in late January. Apple, Asian pear and pear wood should be collected in early February. Scion wood should be cut from the whip-like growth found in the tops of superior quality trees. One year old wood is preferable to older wood and should be of average vigor and well hardened. Wood grown in sunlight is better than that grown in shade. Scion wood can range from 8 to 18”, about the thickness of a pencil, and be free of insects, diseases, and frost injury. Begin grafting whenever weather conditions cause sap to rise freely, and the buds at the top of the tree to swell.
Sources: “Grafting Ornamental Plants and Fruit Trees”, Royal Horticulture Society, www.rhs.org.uk Oregon State University Extension Services, oregonstate.edu, Carol Savon, “Propagation of Plants by Grafting and Budding”, “It’s time to gather scion wood for grafting”
What is a good book about garden design?
The Victoria Master Gardener’s Association (VMGA) Landscape Design Group has some excellent resources listed on their web page. One of the most interesting (in this writer’s opinion) is the book “Plant Driven Design: Creating Gardens That Honor Plants, Place, Spirit” by Lauren and Scott Ogden. The authors write that we don’t have to know all the tenants of design to create an interesting garden. In fact, they say most of the plans taught in landscape architecture programs are formulaic and gardens end up looking like a home improvement project. The Ogdens think that by making plants, their character, structure, individuality, and seasonality the focus of the garden returns gardening to being a relationship between plants and people a happy one. They suggest beginning by observing nature, how plants grow in the wild, where they look their best with other plants. They believe gardening is about curiosity and change, that a garden that is perfect all the time is boring. We want to go out the door and see something different every week. It is human nature to want change. If everything was the same we wouldn’t see it. Unpredictability and imperfection is part of nature. Style is less important that having plants we really enjoy.
Sources: VGMA website, Landscape Design Group, “Plant Driven Design: Creating Gardens That Honor Plants, Place, Spirit” by Lauren and Scott Ogden, Timber Press, 2008
October Clinic Questions:
Can I plant an evergreen hedge in the fall and what kinds of things should I do to prepare the area.
Fall is a good time to plant as the soil is not inundated with water and it isn’t yet cold with frost making it easy to dig. Plants are going into dormancy at this time of year so by getting them in the ground now, they will be in place for their roots to grow the following spring.
Proper preparation when planting your evergreen hedge gets plants off to a good start. Decide on the species you are going to use and investigate the mature width and height and the recommended spacing. Ensure the planting site has adequate drainage and receives enough sunlight for growth requirements.
Prepare the area where the plants will be planted by digging a trench. Soak the planting holes with water and watch to see how long it takes to drain. If it doesn’t there is a problem. You can fix it by either creating a raised bed, installing a drainage pipe, installing a drainage ditch or if it isn’t severe amend with organic matter at the bottom of the dug trench.
Organically rich soil is preferable to help maintain moisture. Supplementing the existing soil with triple mix, compost and or manure will only improve the soils water retention. If you are adding bonemeal or fertilizer make sure to mix all amendments thoroughly with existing soil. Depending on the type and size of plant you have chosen, space the plants accordingly and replace soil around plants tamping down to ensure the plants don’t tip over.
Mulch is an excellent method of adding nutrients to the soil, slowly over time. It also acts as an insulator, maintaining a cool soil temperature, reducing evaporation from the soil’s surface as well as keeping weeds at bay. Ensure the plants are well watered during a dry spell. Top dress with mulch annually.
Sources:
Royal Horticultural Society
Video:
www.rhs.org.uk/videos/advice/Planting-hedges
http://russellnursery.com/plant-a-hedge-row-not-a-hedge/
Why does winter squash taste better if left on the vine till late fall?
Of course you can harvest any time they’ve reached mature size but squash develop more sweetness if left on the vine till the leaves start dying back in the fall.
Winter squash become sweeter after a hard frost or two but they should be harvested and cured if the temperature drops below -5c. Most winter squash become sweeter after a couple of months of storage and can be kept up to six months if stored properly.
Over time, in storage, some of the flesh’s complex starch (dry matter) breaks down into simple sugars and water. The 4 VMGA MEMBER PHOTOSresult is squash with improved flavour - a sweeter and pleasantly moist taste. There is an optimal storage period, which differs for each type of squash; after that the squash may appear to be storing well but usually the flavour will decline.
Sources:
Missouribotanicalgarden.org
grow-it-organically.com
September Clinic Questions:
I have some gray, powdery substance in my vegetable garden (on the foliage and stems of my zucchini, squash, and pumpkins). What is this, is it harmful and what can I do about it?
Given your description of the substance and the time of year, I think your vegetables are being affected by a fungus called powdery mildew. It appears as a white or light gray powdery or furry-textured coating on plants in the late summer and fall. Old leaves are more susceptible than new growth and maintaining vigorous growth helps keep the fungus away.
There are different species of powdery mildews that attack different host plants. Members of the squash and cucumber family are particularly susceptible but other edibles can be affected too such as apples, black currants, gooseberries, grapes, rosemary, and peas. Powdery mildew can also affect ornamental plants such as delphiniums, phlox, rhododendrons, azaleas, and roses.
Powdery mildew typically affects the stems and foliage of plants but sometimes you can also see it on the fruit and flowers. The fungus is present in many places in the garden and can overwinter on plants or in plant debris. The spores of the fungus are spread by wind, rain, insects, or even on the feet of birds. When the right strain of powdery mildew finds the right host plant, the fungus rapidly attacks the surface of the leaves, taking nutrients from the leaf while forming the powdery substance on the leaf.
On vegetables, the fungus typically only affects the leaves and stems but loss of leaves can affect how many squash or cucumbers are produced. Some people recommend removing the affected leaves but others note that the spores have already spread by the time we notice the powdery substance. By not removing the leaves, the plant is likely to continue to get some benefits from photosynthesis. When the affected leaves turn brown and dry up, they can be composted. Just pick the vegetables when they are mature and wash them.
If you notice the powdery mildew early, there’s a few things to try to keep its growth in check. Powdery mildew spores cannot germinate when there is water on the leaves so you can rinse off all the leaves (on both sides) with water at mid-day so the leaves have time to dry before nightfall. Do this several times per week. Another idea was discovered by Canadian researchers: a mixture of milk (e.g., skim, 2%, whole) and water. Different people recommend different ratios of milk to water in the mixture: 10% milk to 90% water, 30% milk to 70% water, or 40% milk to 60% water, always using more water than milk. The proteins in the milk interact with the sun to create an antiseptic effect. To be most effective, the milk mixture can be used preventatively by applying it in bright light every 10 days or so.
Prevention is key with powdery mildew – try to water the morning, rather than the evening, to allow plenty of time for leaves to dry during the day and choose mildew resistant or tolerant cultivars. Check seed catalogues for powdery mildew resistant zucchinis, cucumbers, grapes, and other plants.
Sources:
Royal Horticultural Societyhttps://www.rhs.org.uk/advice/profile?pid=253
Growveg.comhttp://www.growveg.com/growblogpost.aspx?id=242
Master Gardeners Association of BC: http://mgabc.org/content/powdery-mildew-aphid-infestations-early-mid-fall
Sunset Western Garden Bookedited by Kathleen Norris Brenzel, p. 666
Natural insect, weed and disease controlby Linda Gilkeson, page 147-148
I planted a single hosta in my garden about five years ago and now I have a clump growing. Is this OK? Can I divide them and plant some in other parts of my garden or share them with friends?
Hostas are known to be a wonderful foliage plant for shady locations that are easy to grow. They come in a variety of sizes (from miniature to huge!) and colours (e.g., light to dark green to chartreuse to gray and blue). Colour combinations may include white, cream or yellow borders or stripes. The leaf textures vary from smooth to quilted to puckery. The flowers can also be lovely and many are fragrant.
Hostas grow best in good, organically enriched soil with regular feeding during the growing season. Hostas require moisture to thrive and must not dry out for long periods. Clumps expand in size over the years and can remain vigorous without division. Hostas also do well in containers. You can divide a hosta clump to move pieces to another location in your garden or to share it with your luckiest friends or neighbours.
Hostas can be divided in the fall or spring, although late August may be the best time to divide hostas. If doing it in the fall, be sure to do it early enough so that the roots are established before any chance of freezing weather (6-8 weeks before a hard frost). A day or two before you are going to divide the plant, moisten the soil around the clump. On the day of dividing, follow the steps below. Be sure to have the new bed prepared for the division and if you plan to share, have a pot(s) with fresh soil that you can pop the division(s) into so roots remain moist and protected until they arrive at their new home(s).
Steps to divide a hosta:
- Lift the clump with a pitch fork being careful not to damage the growing points
- Place the clump on board or plastic sheet
- With a sharp spade or old kitchen knife, cut between the shoots so you have 4-5 shoots per clump or sections can be prised apart with two pitchforks
- Replant sections in the ground at the same depth they were before you lifted the clump, with shoots poking through the soil surface
- Water the freshly planted plant sections (in ground or pots)
Sources:
Sunset Western Garden Bookedited by Kathleen Norris Brenzel, p. 391 and 700
Royal Horticultural Society https://www.rhs.org.uk/advice/profile?PID=610;https://www.rhs.org.uk/advice/profile?PID=363
American Hosta Societyhttp://www.americanhostasociety.org/Education/hosta_gardening_calendar.htm
August Clinic Questions:
What Should I Do With My Raspberries This Month?
Well that depends on whether you have canes that fruit in the summer or late autumn.
Most hybrid cane fruits (including blackberries) operate on a biennial system with the canes growing during the first year and then flowering and fruiting during their second summer. Once the fruit is picked, cut down the canes to just above the ground; this will make room for new shoots.
If you have late autumn bearing canes, cut them down to just above the ground in early spring before new growth starts.
With both types, after pruning, apply a 2-3" layer of compost or aged manure and water thoroughly.
Is There Any Pruning In My Ornamental Garden I Should Be Doing Now?
Yes, August is a great time to prune some of your woody ornamental trees. Sap bleeding will be at its lowest during the day when the evaporation of water from the leaves will not only reduce the pressure in the zylem (water conducting tube) but will actually create a strong tension in the system, therefore reducing bleeding.
Ornamental trees such as Japanese maples, Beech, Birch, Oak, American Ash, Maples, all take pruning well this time of year.
Remember to clean your tools between trees and even between cuts on the same tree if disease is present. Lysol Brand disposable wipes work great for this.
Here's a helpful clean up hint if you find you get some pitch/resin on yourself while rattling around the garden. If you've got pitch in your hair, slather on some mayonnaise, leave for 15 minutes and comb out slowly; then shampoo. If you have some on your skin, hand sanitizer works wonders!
Source: The Complete Book of Pruning Coombs, Blackburne-Maze, Cracknell & Bentley. Cassell Paperbacks
July Clinic Questions:
How do I get rid of moss in my lawn?
This is a question we hear a lot at the VMGA and there’s a few different ways to tackle this issue.
First, it’s important to recognize that the underlying conditions favouring the moss need to be corrected otherwise whatever you do will be short term.
Here’s some ideas to get started:
- improve perimeter drainage
- apply lime to reduce the acidity in either the spring or fall
- aerate the soil and add a dressing of sand to improve drainage
- water properly – let grass rest during the summer if it’s established (more than two years old) and water deeply just once a month . Frequent sprinkling leads to shallow roots
- mow properly – remove about one third of the blade and mow in a different pattern each time to avoid soil compaction
- remember to leave the clippings on the grass after mowing for a free source of nitrogen
Another option is to replace your lawn entirely with something completely different. Given this summer’s drought and the prospect that climate change will likely lead to more of the same, consider this; conventional turf grass lawns typically consume vast amounts of precious water, are monocultures so frequently encounter problems, do not offer wildlife any refuge, often are a major source of fertilizer and chemical runoff into the environment and finally, they require a lot of work to maintain.
Did you know the average gardener spends up to 100 hours mowing every year?
Instead you could create a garden using native species that after just one year won’t need any watering at all.
Here’s just a few native species to consider, from groundcovers to shrubs to perennials
- Kinnikinnick (Arctostaphylos uva-ursi)
- Salal (Gaultheria shallon)
- Western Red Columbine (Aquilegia Formosa)
- Evergreen Huckleberry (Vaccinium ovatum)
Alternatively, you can learn to love the moss, which is soft, green and never needs mowing!
A few excellent resources to help get started include Native Plant Society (www.npsbc.org)
Naturescape British Columbia(www.naturescapebc.ca)
Make the neighbourhood a better place(Start something in your backyard): A resident’s guide to natural yard care for the Lower Mainland (pdf available online and relevant to all southern BC residents)
How to get your LAWN OFF GRASS: A North American Guide to Turning Off The Water Tap and Going Native by Carole Rubin (published in BC, 2002, Harbour Publishing)
When should I start thinking about planting winter veggies and what works best on our coast?
Despite the beautiful mid-summer sunshine, now is the time to start planning and planting your winter veggies.
According to Helen Chestnut, in the Times Colonist’s Garden Notes, early August is the “ideal time to seed autumn and winter green and salad vegetables such as spinach, radish, corn salad, mustards, mesclun mixes, leaf lettuce and cold hardy lettuces.” She also advises us to check out our local nurseries for “lettuce, kale, cabbage, cauliflower and broccoli transplants for fall, winter and early-spring harvesting.”
Sometimes it’s challenging to know when exactly to seed or use transplants, as well as what kind of protection to prepare for those cold winter months and when to expect to harvest outside of summer months. An excellent resource that includes a planting chart as well as details regarding cold hardy cultivars (e.g. two kinds of romaine lettuce, Winter Density and Rouge d’Hiver are generally cold tolerant) is the West Coast Seeds catalogue. Find one at your local garden centre or go online.
Finally, a fantastic resource for veggie gardeners is Linda Gilkeson, who lives on Saltspring Island and offers a wide variety of workshops in Victoria and beyond. A major proponent of gardening year round, her Year-Around Harvest: Winter Gardening on the Coast, details the benefits of winter gardening (fresh veggies when the cost of produce increases instore), what to grow and when, pest management information, planting plans and much more. Check out Linda Gilkeson’s websitewww.lindagilkeson.ca to order a book or check her workshop schedule.
So now it’s even easier to enjoy eating your own veggies year round without a greenhouse and be the envy of all those who know you!
June Clinic Question:
I’ve got Black Spot on my roses (I think). What can I do about it?
Blackspot, Diplocarpon rosae, is a fungal disease that appears on leaves contributing to overall loss of plant vigor. This disease appears as dark purple/black lesions on both the upper and lower sides of leaves. The fungus moves upwards from leaf to leaf, turning leaves yellow (often but not always) and may eventually defoliate the entire plant. The fungus may live on the ground or in the young stems and buds over the winter.
The fungal spores are spread by moist conditions, such as splashing water and once on the leaves, spread rapidly, ever upwards.
Fortunately, the rose-grower has a number of preventative options:
- Close in vigilance: Regular check ups of your roses will hopefully nip the problem in the bud! :) Inspect your roses often, check for healthy leaves, and remove any that are diseased. Do not compost infected material.
- Sanitation/Hygiene: The fungus lives in leaves on the ground, keep the area tidy of fallen leaves and debris, even during winter.
- Watering: Avoid wetting the foliage, water at ground/soil level. Too much water increases air humidity, a condition the fungus likes!
- Air Circulation and Sunlight: Provide space for air to move and to prevent the fungus moving from rose to rose. Sunlight helps to dry out the dew.
- Pruning: Remove weak, diseased, dead canes. Also prune for internal air circulation. In severe cases, the black spot is visible on the canes, prune back below an area of stem lesions.
- Resistant Varieties: Choose varieties resistant to black spot, however, there is no guarantee the variety will continue to be resistant. The Royal Horticultural Society suggests the older species are less affected overall.
Organic Spray: To change the pH level on the leaves, mix a foliar spray of 1tsp baking soda to a liter of water and 1 tsp of dish soap (non-bleaching) on both sides of the leaves. The soap helps to keep the baking soda mixture on the leaf. Repeat weekly and after rain.
Disposal: This is a determined fungus. We suggest you dispose of diseased leaves and canes in the garbage, or by burning. Do not introduce into the garden compost or add to the municipal collection sites.
Sources:
Royal Horticultural Society, Rose black spot https://www.rhs.org.uk/advice/profile?PID=270
Missouri Botanical Garden, Black Spot of the Rose http://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/pests-and-problems/diseases/fungal-spots/black-spot.aspx
May Clinic Questions:
What is an organic food I can feed my roses that will encourage beautiful blooms?
Roses are heavy feeders and food does encourage beautiful blooms. In addition, roses benefit from ongoing organic inputs and pre-bloom care.
Soil and Mulch: Feed and care for the soil!! Well draining organic, non-compacted soil to allow roots to spread and foster uptake of nutrients and water. A layer of organic mulch keeps the soil cooler, roots happier and reduces competition from weeds. As the mulch breaks down the roses will have a further supply of nutrients.
Fertilizer: Keep the proportions of nitrogen, phosphorous and potassium in the single digits. Higher ratios are not better. Start in the spring with a well-balanced, slow release fertilizer. Many rose growers use a granular, organic product. Apply a new layer of compost. Throughout the rest of the growing season apply monthly an organic liquid fertilizer such as fish/kelp or alfalfa/manure tea. Water well before applying liquids.
Many gardeners have used banana peels, chopped up and spread around the plant.
Other Considerations: Other aspects of care to encourage blooming include site selection, pruning to select strong, disease free canes, watering below foliage to discourage mildew and fungus.
Sources
Good Earth R.O.S.E. Care Monthly Guide (the organic side of the American Rose Society) http://www.organicrosecare.org/articles/calendar_socal.php
Spring Valley Roses Step by step Guide http://www.springvalleyroses.com/inthegarden/fertilizing.html
American Rose Society includes suggestions to compliment different styles of gardening from the casual to the exhibitor. http://www.rose.org/rose-care-articles/fertilizers-when-and-how/
Doug Hamby, Fernbank Science Center Atlanta , Georgia. Video: http://video.about.com/flowers/5-Tips-for-Growing-Bigger-Rose-Blooms.htm
What can I feed my tomatoes?
Tomatoes are a popular, edible annual requiring lots of sunlight, enough water and good nutrition. Grown in the ground or a container, tomatoes may grow in many different types of soil but like neutral Ph and soil amended with organic matter at planting time. Great soil gives the plants a good start but may not provide sufficient nutrients for the growing season.
According the University of Missouri Extension Site, too much nitrogen encourages leaves and green growth rather than fruiting. Thus a fertilizer low in nitrogen, high in phosphorus and with a medium to high amount of potassium. Secondary and micronutrients can be delivered through organic matter. The site recommends a first application of fertilizer when the plants are 1/3 grown, and a second two weeks after the first tomatoes are picked and the third a month later. The ratio of NPK is 10-10-10. Throughout the growing season add mulch to control moisture loss, weeds and prevent water from splashing plants.
The Canadian Gardener website recommends fertilizing twice monthly, using a water-soluble fertilizer (NPK 15-15-30). Here the amount of nitrogen and phosphorous is lower while potassium is higher.
Tomato Dirt is another site with interesting tomato information and a list of organic sources.
Sources:
University of Missouri Extension fact sheet http://extension.missouri.edu/p/G6461
Canadian Gardener http://www.canadiangardening.com/gardens/fruit-and-vegetable-gardening/10-starter-tips-for-growing-tasty-tomatoes/a/42177/2
Tomato Dirt http://www.tomatodirt.com/preparing-your-soil.html
Ed Hulme Seeds, suggests we may over-fertilize https://www.humeseeds.com/sumtom.htm
April Clinic Questions:
What can I plant under a Walnut tree?
Planting under a Black Walnut tree (Juglans nigra) can indeed be a major challenge – according to Canadian Gardener magazine. This is because the roots, leaves, husks and buds produce a substance called juglone, which can be toxic to many plants. The poisonous zone is large too – extending 20 to 30 metres from the trunk – so it’s important to try to clean up tree debris (do not compost) and add organic materials. Some plants that are juglone tolerant and are worth trying include Virginia Creeper, Japanese Maple and European Wild Ginger. Check out this article in Canadian Gardener for more planting ideas: http://www.canadiangardening.com/plants/trees-and-shrubs/what-will-grow-under-a-black-walnut/a/29797
What can I plant under a Conifer?
A walk in the woods is in order! Typically the growing conditions underneath Conifers are considered challenging, often dry and shady to boot. However, a keen gardener can turn this challenge into an advantage simply by considering native plants. As the authors of “The New Twelve Month Gardener” so aptly write, “A walk in the woods will teach you a great deal about texture, colour and natural layering.”
Some planting ideas could include shrubs such as Huckleberry, Snowberry bush, Oregon Grape, Red Flowering Currant (a favourite of hummingbirds) or Salal. Perennials to try include ferns, foxgloves, bleeding hearts or gentians and bulbs such as camas, wild tiger lily and dog-tooth violet. Non-natives like Hardy Geraniums and Epimediums will also thrive in dry shade.
Check out some of the lovely native plant gardens nearby for inspiration – the Horticulture Centre of the Pacific, Government House and Swan Lake Nature Sanctuary.
What soil is best for flowering container garden?
This question can illicit all sorts of “animated discussion” among keen gardeners – many have their very own tried and true formula for container soils that they swear is the best of the best. Trying to keep everyone happy, I’ve turned to my trusty steed The Container Expert, by Dr. D. G. Hessayon for advice.
Clearly, as containers provide a small growing space, top quality growing mediums are important. Dr. Hessayon says that ordinary soil from the garden won’t do the trick, because it will compact, depriving plant roots of the air and moisture they need. Commercial planter soil mixes provide the right balance between good drainage and water retention.
Look for bags of either soil-based or soilless compost. The first type is best for permanent planting, as it’s heavier and holds nutrients better. For hanging baskets look for soilless compost , which is light and clean but is hard to rewet if it dries out too much. Options here include peat-based and coir-based - I think it’s important to note that peat is not an environmentally sustainable choice, so I always buy coir, a product that was previously thrown away from coconut husks and is the favourite choice of the Eden Project in Cornwall, England.
You will have to provide nutrients to your container plants. Many commercial soil mixes already contain granular fertilizer. Check labels for time limits, then provide your own fertilizer in either slow release pellet form or liquid fertilizer.
When is it safe to plant vegetables outside? What are the growth requirements?
This is a tricky question as there’s no hard and fast rule for all vegetables. For example, broad beans can be sown in February, and even in October and November (although I’ve had no luck with such early sowing) for a crop about three months later – six months for fall plantings.
Tomatoes, on the other hand, in a typical year in our area, can be successfully transplanted in late May or early June when the nighttime temperatures are reliably 10 degrees Celsius or higher.
And some vegetable continue on through the winter!
The same goes for growth requirements – each veggie has its own needs and wants for tip top production.
West Coast Seeds has a marvellous catalogue and website that clearly details timing and growing conditions for many, many vegetables from artichokes to turnips. There’s even an online Planting Chart available for download at www.westcoastseeds.com This is an excellent starting place for new vegetable gardeners.
February Clinic Questions:
What are the different kinds of garlic?
There are two main groups of garlic for the home gardener to enjoy. These are the Hardneck group and the Softneck group. In our BC climate, Hardneck garlic tends to be more reliable. Hardneck varieties such as Red Russian, Wengers Russian and Gourmet Red also supply savvy cooks with garlic scapes! (Cut off the tall flower stem that grows up and out of the bulb as they curl over, to prevent energy from going to seed production instead of the bulb itself.) Scapes can be stir fried or steamed.
Late October-November is the best time for you to plant garlic and it can be harvested in July. A reliable way to tell if your garlic is ready is to watch the leaves wither and yellow to about 2/3. Hang in a cool dry area until the skins appear papery and white; the bulbs can be stored for 4-6 months.
Garlic can be easily grown in containers as long as they are well draining, non frost-cracking and can be kept moist from planting to harvest time.
Garlic is a great companion plant in your ornamental or edible garden too; it is a natural organic repellent for aphids and spider mites!
Sources: Encyclopedia of Natural Insect and Disease Conrol, Rodale @ 1984 , A Year on the Garden Path, C. Herriot @ 2005
Can I start seeds now?
There are several seeds that you can start indoors in February in Coastal BC. Bottom heat and full spectrum fluorescent lights will help ensure success. Most seeds germinate most reliably at a soil temperature of 20-25C. Covering the seed trays with plastic and having bottom heating mats or heating coils are effective and low cost both in energy terms and purchase price. Bright light is often crucial for both germination as well as plant growth, thus, sow the seeds thinly and lightly with just a thin layer( a good rule of thumb is twice as deep as the size of the seed) of sterile potting mix over top the seeds. Consistent, soft watering is also important. A brass water mister on the end of your hose is a good tool to use at this stage of plant development.
Some edible seeds you can start now include: artichoke, leeks and asparagus. Some herbs to start now include slower germinators such as lavender, rosemary, oregano and bergamot. In addition, you can get a head start on your ornamental flower garden by starting annuals and perennials such as marigolds, viola and columbines. Of course, there are many more plants you can start now and a good planting chart can be found on the West Coast Seed website at the following link:
https://www.westcoastseeds.com/garden-resources/west-coast-seeds-planting-charts/
Source: West Coast Seed Guide 2005, 2014
November Clinic Questions:
Can I grow tomatoes in Victoria during the winter months?
Tomatoes require a certain number of growing degree-days in order to bloom, set (assuming pollination) and ripen plus sufficient hours of light. Tomatoes need warmth: warm days in the 15-17 C range and night temperatures above 10 C (the base temperature is 10 C meaning tomatoes will not grow below 10 C). At least 8 hours of sunlight, ideally in full sun. It would be possible to provide these conditions in a heated greenhouse, but would be expensive to maintain.
Source: Colorado State University Extension athttp://www.ext.colostate.edu/mg/Gardennotes/717.html
What part of the Dahlia did the Aztec’s eat?
Distinct from the fancy Dahlia of our gardens, the Aztec diet included the indigenous Dahlia pinnata found in the mountains of southern Mexico. This dahlia plant is very tall, up to 20 feet, tree-like and was known as acocotli or “water cane” according to the 1570 account of physician Francisco Hernandez. The tubers were eaten and the stems used as a water source when travelling. The Dahlia is the national flower of Mexico.
Sources: Stanford Dahlia Project and the Victoria Horticultural Society
What can I plant in my fall container? I have an evergreen perennial already – what else do I need?
A garden in a freeze proof pot! Remember the basic design principals: Colour, Shape, Texture, Form, Line and Scale. Choose combinations pleasing to the eye, proportionate to the surrounding landscape. More contrast means greater drama! Being a mini-garden, selection is crucial to health and growth plus size and site of your container.
Ensure that each plant will work with available container space, anticipated moisture levels, hardiness, sun/light and soil conditions for your container’s site and seasonal weather changes. Growth rate and mature plant size are also important considerations.
Use the evergreen perennial you already have and combine it with two or more of these year round interest evergreen plant possibilities:
- Carex (Sedges)
- Dwarf conifers – a wide variety of fir, pine, cypress, yew and spruce
- Autumn Fern - Dryopteris erythrosora
- Sword Fern - Polystichum munitum
- Holly Fern - Polystichum makinoi
- Hart's-Tongue Fern - Asplenium scolopendrium
- Deer Fern - Blechnum spicant
- Hellebores
- Heathers
- Heuchera - many to choose from
- Hebes - hardier varieties
- Podocarpus
- Rhododendrons - dwarf/compact varieties
- Saracocca (sweet box)- great for by the doorway
- Skimmia - dwarf/compact varieties
Your possibilities are endless.
A few other tips to keep in mind
- plant in multiples of 3, 5, 7 ...... odd numbers are pleasing to the eye
- don’t be afraid to overplant
- container plantings lose at least one zone in hardiness (versus being planted in the ground), and more for elevations (higher floor balcony/terrace)
- use a potting soil mix that will allow for good drainage
- don’t panic, if your plants eventually get too large for your container, it’s easy to relocate them in your garden or give themaway.
Enjoy your new container!
Sources: The Pacific Northwest Gardeners Book of Lists, Ray and Jan McNeilan, 1997; Container Gardening, Fine Gardening vol. 7, 2010, Perfect Plant Perfect Place, Roy Lancaster, 2002 and Great Plant Picks www.greatplantpicks.org