Astrophytum asterias var. asterias
This species is native to Mexico: it grows in semi-desertic climate areas on saline, calcareous or loam soils on hills, along the sides of dry river beds, on grassalands or thorny shrubs.
Astrophytum asterias is a beautiful flat barrel cactus. It usually grows in solitary stems: this is grey-green speckled with tufts of white hairs. The stem presents narrow and distinct vertical grooves, which divide it into (usually) 8 broad ribs: these form triangular sections on the stem. The round areoles form a line up to the centre of each rib, and usually they are covered in white – dirty-yellow hairs. Cultivated plants may bloom anytime during warm season: the flowers are apical, diurnal, yellow with orange-reddish throats.
Astrophytum asterias is a relatively easy-to-grow species. It needs a mineral, well-drained soil with little organic matter. Re-pot every 2 years, using containers with good drainage. During spring and summer use a low nitrogen content fertilizer to make it grow faster; potassium is helpful for the plant health. Water sparingly from March till October, letting the soil getting dry before watering again. To avoid root rot, keep it dry from the beginning of autumn to the end of winter. It is hardy to -5°C, but during cold months keep it in a cool place. It does well from full sun to light shade – in this case, its colour will get richer and darker.
Propagation can be easily done by seeds: anyway, it is necessary to avoid strong lights and dry conditions.
Astrophytum asterias is sometimes confused with Peyote (Lophophora williamsii), but there is no evidence of hallucinogenic effects of this plant.