Sempervivum arachnoideum
Sempervivum arachnoideum
Safety & Hazards
None known
Cultivation Details
Prefers a well-drained gritty soil in full sun[1]. Succeeds in any sandy soil, doing well in very little soil in rock crevices, walls, paths etc so long as there is sufficient humus[2, 1]. Prefers growing on acid rocks, though it also succeeds on calcareous ones[3]. Established plants are drought tolerant[1]. Strongly dislikes winter wet[1]. Plants are not very tolerant of weed competition[PFAF]. Polymorphic, this species is split into a number of sub-species by some botanists[1]. Individual rosettes die after flowering, but produce a number of offsets that continue to grow[4]. Hybridizes with a number of other members of this genus[1].
Propagation
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[PFAF]. 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. Stem cuttings. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Sempervivum+arachnoideum>
Pollinators
Insects
References
- [1]The New RHS Dictionary of Gardening. 1992. — Huxley. A. · MacMillan Press · 1992 · ISBN 0-333-47494-5 ↩︎Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
- [2]RHS Dictionary of Plants plus Supplement. 1956 — F. Chittendon. · Oxford University Press · 1951 · ISBN - ↩︎Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaced in 1992 by a new dictionary (see [ 200 ]).
- [3]Gardening on Walls — Grey-Wilson. C. & Matthews. V. · Collins · 1983 · ISBN 0-00-219220-0 ↩︎A nice little book about plants for growing against walls and a small section on plants that can grow in walls.
- [4]The RHS Gardener's Encyclopedia of Plants and Flowers — Brickell. C. · Dorling Kindersley Publishers Ltd. · 1990 · ISBN 0-86318-386-7 ↩︎Excellent range of photographs, some cultivation details but very little information on plant uses.
- [5]Encyclopaedia of Medicinal Plants. — Chiej. R. · MacDonald · 1984 · ISBN 0-356-10541-5 ↩︎Covers plants growing in Europe. Also gives other interesting information on the plants. Good photographs.
- [PFAF]Plants for a Future — pfaf.org ↩︎