Scientific Name
Sempervivum arachnoideum subsp. tomentosum (C.B.Lehm. & Schnittsp.) Schinz & Thell.
Common Name(s)
Woolly Cobweb Houseleek, Cobweb Hen and Chicks
Synonym(s)
Sempervivum tomentosum, Sempervivum laggeri, Sempervivum arachnoideum var. laggeri, Sempervivum webbianum
Scientific Classification
Family: Crassulaceae
Subfamily: Sedoideae
Tribe: Sedeae
Subtribe: Sedinae
Genus: Sempervivum
Etymology
The subspecific epithet "tomentosum" (pronounced "toh-men-TOH-sum") means "having a mass of rough hairs" and refers to the usually abundant cobwebby hairs on the leaves of this subspecies.
Origin
Sempervivum arachnoideum subsp. tomentosum is native to the mountains of central and southern Europe.
Description
Sempervivum arachnoideum subsp. tomentosum is a mat-forming succulent that forms rosettes of thick, fleshy, obovate, mid-green to red leaves densely covered in white cobweb-like hairs. The rosettes can grow up to 1.4 inches (3.5 cm) in diameter. The cobwebby hairs are usually abundant, but disappear in the fall.
The pink, star-shaped flowers are borne in flat cymes on stalks that can grow up to 6 inches (15 cm) tall. They appear in summer and can reach a diameter of up to 0.6 inches (1.5 cm).
Hardiness
USDA hardiness zone 4a to 10b: from -30°F (-34.4°C) to 40°F (4.4°C).
How to Grow and Care
Because of their variability, Cobweb Houseleek easily adapts to local conditions. Due to the small gene pool, they become a form or variety quite quickly, perfectly adapted to the local conditions of heat and cold, the amount of snow or rain, and at what times of the year.
Growing in a container, rock garden, scree bed, wall crevice, trough, or alpine house is relatively easy. They are ideal in so many ways. They quickly start forming tight clusters of rosettes, filling in Sempervivum walls, mosaics, and topiary. Their shallow yet fibrous root systems hold soil in place even in vertical plantings. After the rosette blooms and sets seed, it will die, but many offsets will take root.
Plant in well-drained succulent soil mix in full sun to light shade. Water regularly during the growing season and allow the soil to dry out before watering again. Water very little during the winter months.
See more at How to Grow and Care for Sempervivum.
Links
- Back to genus Sempervivum
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus
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