Astrophytum asterias (Zucc.) Lem.

Description

Stem hemispherical in shape, up to 6-8 cm in diameter, depressed at the centre, dark green. With age, in cultivation, it tends to grow in height, becoming taller than it is wide. Generally with 8 ribs separated by shallow furrows. The epidermis is patterned with rather sparse white dots, while the areoles, set very close together, are 3-4 mm across, with dense, short hairs. The flowers, produced continuously until late autumn, are yellow, up to 6 cm wide, with a dark red throat. The seeds, characteristic of the genus, are large and helmet-shaped. In the wild it barely protrudes from the ground and, during the dry months, it shrivels to the point of disappearing from view, covered by dust and stones.

Cultivation

is the only variety of Astrophytum that is difficult to grow. It dislikes stagnant humidity, especially when young. A purely mineral soil is, therefore, absolutely necessary, whilst between one watering and another the soil in the pot should become completely dry

Propagation

being a solitary plant, reproduction is obtained exclusively from seeds. All Astrophytum species hybridise easily with one another. Indeed, the splendid plant shown in the entry betrays a distant kinship with Astrophytum ornatum (note the spines emerging from the areoles and the slightly acute ribs).