Astrophytum

Astrophytum is a small cactus genus of six species native to the limestone deserts and semi-arid plains of northern Mexico and southern Texas. The genus is celebrated among collectors for its outstanding ornamental qualities: the star-shaped cross-sections suggested by the genus name (Greek for 'star plant'), and surface markings of white floccose dots. Prominent species include A. asterias (Sand Dollar Cactus or Bishop's Cap), A. myriostigma (Bishop's Miter), and A. ornatum (Star Cactus). A. asterias in particular, with its densely stippled surface and large yellow flowers, is considered one of the most desirable cacti and can command high prices. Mature plants are 5–30 cm across. All prefer full sun with light summer shading, excellent drainage in a slightly alkaline substrate, and seasonal watering. Growth is extremely slow. Grafting is commonly practiced to accelerate development.

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