# Star Cactus / Sand Dollar Cactus (Astrophytum asterias)

> An iconic spineless cactus defined by a flattened-globose, disc-like stem divided into eight low ribs adorned with prominent woolly areoles. Its epidermis is decorated with tiny white flecks of trichomes, producing striking yellow flowers with red centers from the apical meristem in summer. It is a slow-growing, highly prized collector's plant possessing a sensitive taproot susceptible to excess moisture.

- **Scientific Name:** *Astrophytum asterias*
- **Botanical Family:** Cactaceae
- **Care Difficulty:** Moderate (2/5)
- **Cold Hardiness:** -2°C (USDA Zone 9b)
- **Pet Safety / Toxicity:** Pet-Safe (Non-toxic to cats and dogs)
- **Canonical URL:** https://sukulentler.com/en/species/astrophytum-asterias
- **Markdown Source:** https://sukulentler.com/en/species/astrophytum-asterias.md
- **Botanical Photo:** https://sukulentler.com/assets/images/articles/species_astrophytum_asterias.webp?v=1793836894

## Light & Sun Exposure

At least 5-6 hours of bright, filtered sunlight daily; provide light afternoon shade during peak summer to prevent scorching.

## Watering Schedule & Method

Strict soak-and-dry protocol; water thoroughly only after substrate is bone dry during active growth. Keep entirely dry in winter dormancy.

## Soil & Gritty Mix Formula

70% Inorganic grit (pumice, lava rock, zeolite) + 30% screened cactus potting soil.

## Cold Tolerance & Overwintering

-2°C (USDA Zone 9b)

## Propagation Methods

Seed propagation in warm spring to early summer (solitary habit precludes vegetative stem cuttings).

## Available Language Editions

- [TR: Yıldız Kaktüsü / Deniz Kestanesi Kaktüsü (Astrophytum asterias)](https://sukulentler.com/tr/turler/astrophytum-asterias.md)
- [DE: Seeigelkaktus / Sternkaktus (Astrophytum asterias)](https://sukulentler.com/de/arten/astrophytum-asterias.md)
- [ES: Falso Peyote / Cactus Estrella (Astrophytum asterias)](https://sukulentler.com/es/especies/astrophytum-asterias.md)