Every serious gardener knows the cobweb houseleek (Sempervivum arachnoideum), or I suppose I should say every serious ROCK gardener. Which the plant pictured above is not, by the way. As I was skimming over my pictures from last year I noticed it and thought: why is it that I have never seen this grown in very many gardens? This is Sempervivum ciliosum var borisii, from the Balkans. It does not have cobwebbing, but fine cilia, or hairs around the margins of the leaves. It makes every bit as lovely of mats and mounds as its stunning cobwebby cousin, but the flowers are a soft yellow rather than the chalky pink of its better known congener.
There is another form of this species, a cultivar named 'Mali Hat' for the Balkan mountain where it was collected. I grow it too: similar only the rosettes are stained reddish.
Succulents are staging a major come back in gardens and especially in container gardens. Here is one that is incredibly cold hardy, beautiful all times of year with lovely flowers to boot. Why is it not in your garden? I, for one, would not be without it!