Sempervivum arachnoideum

Sempervivum arachnoideum, the cobweb house-leek,^[1] is a species of flowering plant in the family Crassulaceae, native to European mountains, in the Alps, Apennines and Carpathians. Growing to 8 cm (3 in) tall by 30 cm (12 in) wide, it is a rosette-forming succulent perennial, valued in cultivation for its ability to colonise hot, dry areas via offsets.^[2]

The specific epithet arachnoideum refers to its furry central rosettes (long ciliate leaf margins), resembling spider webs.^[3]

It flowers in July, with pink flowers that are raised on stems and are hermaphroditic (having both male and female organs).

This plant,^[4] and the subspecies Sempervivum arachnoideum subsp. tomentosum,^[5] have gained the Royal Horticultural Society's Award of Garden Merit.^[6]

References

^ BSBI List 2007 (xls). Botanical Society of Britain and Ireland. Archived from the original (xls) on 2015-06-26. Retrieved 2014-10-17.
^ RHS A-Z encyclopedia of garden plants. United Kingdom: Dorling Kindersley. 2008. p. 1136. ISBN 978-1405332965.
^ Harrison, Lorraine (2012). RHS Latin for gardeners. United Kingdom: Mitchell Beazley. p. 224. ISBN 9781845337315.
^ "RHS Plant Selector - Sempervivum arachnoideum". Retrieved 5 March 2021.
^ "RHS Plantfinder - Sempervivum arachnoideum subsp. tomentosum". Retrieved 9 November 2018.
^ "AGM Plants - Ornamental" (PDF). Royal Horticultural Society. July 2017. p. 96. Retrieved 9 November 2018.