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Common Name: Cobweb Houseleek
Sempervivum arachnoideum is a Evergreen Perennial up to 0.10 metres tall.
It is harvested from the wild for local use as a medicine..
Amongst rocks and stones in the cooler regions of Europe, usually on siliceous soils[
Prefers a well-drained gritty soil in full sun[
]. Succeeds in any sandy soil, doing well in very little soil in rock crevices, walls, paths etc so long as there is sufficient humus[
]. Prefers growing on acid rocks, though it also succeeds on calcareous ones[
]. Established plants are drought tolerant[
]. Strongly dislikes winter wet[
]. Plants are not very tolerant of weed competition[
Polymorphic, this species is split into a number of sub-species by some botanists[
Individual rosettes die after flowering, but produce a number of offsets that continue to grow[
Hybridizes with a number of other members of this genus[
The leaves are emollient, haemostatic, ophthalmic and sedative[
]. The crushed plant, or its juice, is applied externally to boils, wounds etc and is also used to stop nose bleeds[
]. The slightly warmed juice has been used to relieve ear inflammations and toothaches can be relieved by chewing on the leaves[
]. When macerated and infused in vinegar, the plant can be used to get rid of warts and corns[
]. The leaves are harvested in the summer and are best used when fresh since they are difficult to dry properly[
The leaf pulp is used to make a cooling face mask for reddened or sunburnt skin[
Seed - surface sow in early spring in a cold frame. It usually germinates in 2 - 6 weeks at 10°c. Prick out the seedlings into individual pots when they are large enough to handle and grow them on in the greenhouse for their first winter. Plant them out into their permanent positions in the summer if they have made sufficient growth, otherwise grow them on for a further year in pots before planting them out[
Division of offsets in spring or early summer. Larger divisions can be planted out direct into their permanent positions. We have found it best to pot up the smaller divisions and grow them on in a lightly shaded position in a cold frame, planting them out once they are well established in the summer. Plants can also be divided in September but these divisions should be overwintered in a greenhouse.