I love sempervivums - even though they look fragile, they are remarkably tough. It was -36 C when we moved back to BC from Saskatchewan 20 years ago, so I went outside with a pickax and chipped some sempervivums out of the frozen ground. They didn't just survive, they flourished and with time offshoots filled pots on a deck. By a bit of good luck, when we moved five years ago we saw the metal roof of the shed we look at from our deck offered a perfect setting for a small rock garden - a few bags of small stones and soil later, and I had a home for my much-travelled sempervivums. The roof gets hot so I watered for the first year to help establish the plants and last year I lifted up the mats of plants with pancake flippers to add an inch of soil, but other than that, they have required no care. Luckily the hot, dry conditions and minimal soil seem not to favour seed germination or weed growth.
