# Cobweb Houseleek (Sempervivum arachnoideum)

> Native to high-altitude rocky screes across the European Alps and Pyrenees, this mat-forming alpine succulent is renowned for its architectural rosettes. Delicate white trichomes stretch between leaf tips, creating a dense cobweb-like canopy that reflects intense UV radiation and minimizes moisture loss. Individual monocarpic rosettes produce starry pink-red flowers on short cymes before dying, having already established a carpet of stoloniferous offsets.

- **Scientific Name:** *Sempervivum arachnoideum*
- **Botanical Family:** Crassulaceae
- **Care Difficulty:** Easy (1/5)
- **Cold Hardiness:** -30°C (-22°F, USDA Zone 4b)
- **Pet Safety / Toxicity:** Pet-Safe (Non-toxic to cats and dogs)
- **Canonical URL:** https://sukulentler.com/en/species/sempervivum-arachnoideum
- **Markdown Source:** https://sukulentler.com/en/species/sempervivum-arachnoideum.md
- **Botanical Photo:** https://sukulentler.com/assets/images/articles/species_sempervivum_arachnoideum.webp?v=1794387677

## Light & Sun Exposure

Requires full sun for at least 6 hours daily; intense natural light ensures dense cobweb trichome production and tight rosette formation.

## Watering Schedule & Method

Follow the soak-and-dry method; let the substrate dry out completely between waterings and withhold almost all supplemental water during freezing winter dormancy.

## Soil & Gritty Mix Formula

70% inorganic grit (pumice, crushed lava rock, coarse granite grit) + 30% organic succulent potting soil.

## Cold Tolerance & Overwintering

-30°C (-22°F, USDA Zone 4b)

## Propagation Methods

Separation and rooting of stoloniferous offsets ('chicks') in spring or early summer, or by alpine seed sowing.

## Available Language Editions

- [TR: Örümcek Ağı Damkoruğu (Sempervivum arachnoideum)](https://sukulentler.com/tr/turler/sempervivum-arachnoideum.md)
- [DE: Spinnweb-Hauswurz (Sempervivum arachnoideum)](https://sukulentler.com/de/arten/sempervivum-arachnoideum.md)
- [ES: Siempreviva de telarañas (Sempervivum arachnoideum)](https://sukulentler.com/es/especies/sempervivum-arachnoideum.md)