Cobweb houseleek

Sempervivum arachnoideum | Also known as: Spiderweb hens and chicks | Rating: 0 votes | Print / Pdf

A mat-forming evergreen perennial, sempervivum arachnoideum is more commonly known as the cobweb houseleek, and one look at it reveals why. Its dense, succulent rosettes comprise thick, triangular leaves that end in a spiky point, with a network of light silvery hairs covering them, resembling a cobweb. A fast spreader, even in poor growing conditions, it is a valued groundcover option, and in summer it produces tall fleshy red stems lined with red ovate leaves, topped with star-shaped, dark pink blossoms. Ideally suited to gravel beds and rockeries, the cobweb houseleek thrives in fertile, well-drained soil in full sun but is no fan of wet weather. Pruning after flowering is advised

Rate it:
Known dangers?
  • no
Height [m]
  • 0.05
Spread [m]
  • 0.5
Dominant flower colour
  • Pink
Flower Fragrance
  • No, neutral please
Flowering seasons
  • Early summer
  • Mid summer
  • Late summer
Foliage in spring
  • Blue or grey-blue
Foliage in summer
  • Blue or grey-blue
Foliage in Autumn
  • Blue or grey-blue
Foliage in winter
  • Blue or grey-blue
Propagation methods
  • seed
  • offsets
Growth habit
  • Compact
  • Creeping
  • Mat-forming
  • Acidic
  • Neutral
  • Alkaline
Hardiness zone
  • Z5-8
Heat zone
  • H8-5
Winter temperatures [°C]
  • -29 - -7
Heat days
  • 30 - 120
  • well-drained
Soil type
  • sandy
  • loams
Sun requirements
  • Full sun
  • Exposed
  • Sheltered
Standard category
  • Cacti & succulents
  • Succulents
Grown for
  • Ornamental Foliage
Creative category
  • Kid Approved
  • For Beginners
  • For every season
  • Tough survivors
Garden type
  • Indoor or winter garden
  • Cottage garden
  • Rock garden
  • Containers
Garden spaces
  • Flower beds
  • Walls, trellises and pergolas
  • Ground cover
Gardening expertise
  • beginner
Time to reach full size
  • up to 10 years
10 Related plants


PLANTS Sempervivum

Garden plants of the Sempervivum genus are amongst the most peculiar to have, but they are also amongst the most spectacular, especially in terms of colour. A great choice for groundcover, the foliage itself generally comprises succulent leaves in rosettes and can be green, purple, rosy pink or copper red. Some cultivars can also have fine hairs growing over their rosettes. Clusters of star-shaped flowers emerge in summer, also in a variety of bright colours. Known as Houseleeks, Sempervivums produce flowers that bloom on thick stems grown from each rosette centre. It thrives in well-drained, slightly alkaline soil and love locations in full sun.

Woolly cobweb houseleek

PLANTS Sempervivum arachnoideum subsp. tomentosum | -29°C - -7°C beginner Full sun

A vigorous spreader and mat-forming evergreen perennial, sempervivum arachnoideum subsp. tomentosum appears the same as its principal species, sempervivum arachnoideum. The key difference is a thicker silvery fur, covering the dense, dark green, red-flushed rosettes, thus earning the plant the common name, the woolly cobweb houseleek. In summer, it produces tall, fleshy red stems topped with star-shaped, dark pink blossoms with sword-shaped, hairy petals and a yellow eye from which red stamens extend. Ideally suited to gravel beds and rockeries, the woolly cobweb houseleek thrives in fertile, well-drained loamy or sandy soil in full sun, and is no fan of wet weather. Pruning after flowering is advised.

Sempervivum calcareum

Limestone houseleek

PLANTS Sempervivum calcareum | -46°C - -1°C beginner Full sun

A mat-forming, evergreen perennial, sempervivum calcareum is one of the more attractive hardy succulents to feature in your garden. Its dense rosettes of thick, ovate, spike-tipped leaves are mainly grey-green, but some tips are reddish-purple to add a greater texture to its appearance. In summer, it produces erect and slightly hairy stems, which are topped with sparse clusters of rose-pink blossoms. It is commonly known as the limestone houseleek, mainly due to its preference for rockeries and gravel beds. Happiest in moist but well-drained loamy soil in full sun, it dislikes cold and wet weather. A sheltered location is required, though cultivating indoors is a popular solution. Pruning after flowering is advised.

Sempervivum tectorum

Common houseleek

PLANTS Sempervivum tectorum | -34°C - -7°C beginner Full sun

Tiny bi-coloured rosettes make sempervivum tectorum one of the most popular mat-forming evergreen succulent perennials around. The pin-sharp, ovate leaves in its dense rosettes are mainly dark green but its outer leaves are blue-green, flushed red nearing the tip. It is this feature that has inspired the common name, the red-leaved houseleek, though it is more readily known as the common houseleek. In summer, thick red stems grow from the centre of individual rosettes and produce loose clusters of dark pink or purple, star-shaped flowers. The common houseleek thrives in moist but well-drained sandy or loamy soil in full sun but sheltered locations. Perfect for gravel beds and rockeries, cultivating indoors is popular too. Pruning after flowering is advised.