Species and Cultivars to Select
After learning how easy it is to care for these plants, it’s time to take a look at the different species in more detail as well as some fabulous cultivars.
Asterias
Known as sand dollar, sea urchin, star, Texas star cactus, or star peyote, A. asterias reaches one to two inches tall and two to six inches wide at maturity.
And though the round, squat shape of this plant resembles peyote, A. asterias contains no hallucinogenic compounds!
This astrophytum is spineless, brownish green in color, covered with small white flecks, and has wooly areoles that form lines going down the center of each rib, of which there are four to 13.
The flowers are yellow with red centers.
Since these plants are endangered, it’s illegal to collect them from the wild. There are plenty of seed-grown options in cultivation.
It can be tricky to know if plant nurseries have sustainable practices without interviewing them. If in doubt, choose a cultivated variety of A. asterias instead.
‘Super Kabuto’ is perhaps the most popular A. asterias cultivar. These plants are covered in attractive, large white flecks.
The flocking on different specimens will vary in its exact pattern – some are so covered in flecks that they are almost completely white, others have large woolly spots or V-like patterns.
Capricorne
Named for its curved spines, A. capricorne is commonly called goat’s horn cactus.
This globe-shaped astrophytum has a single stem that becomes more columnar as it matures, eventually reaching up to six inches wide and four feet tall.
Goat’s horn cactus is green and covered to varying degrees with white flecks. Its spines grow in clusters of five to 10, and it has eight ribs, with areoles that grow vertically along the ribs.
Flowers on goat’s horns cacti are yellow with red centers.
Caput-medusae
With a species epithet that means Medusa’s head, A. caput-medusae was formerly classified in a different genus, as Digitostigma caput-medusae.
When you look at this plant, you don’t see a globular or columnar stem, but instead a bunch of unruly-looking protuberances that inspire its species name.
Those protuberances, or tubercles, as they are more commonly called, are covered with white flocking and emerge from a tiny, ground level stem that is covered in bristles.
Plants can reach up to seven and a half inches tall and wide, and bear yellow blooms at the ends of their protuberances.
This astrophytum is critically endangered as a result of overcollection and grazing pressures.
Coahuilense
A species that is sometimes known by the common names bishop’s cap, bishop’s miter, or monk’s hood cactus, A. coahuilense is easily confused with the more widely available A. myriostigma.
With five ribs and growing in a globe or columnar shape, this bishop’s cap reaches up to eight inches tall and up to four inches wide at maturity.
The skin is densely covered with white flecks, giving this spineless species a gray appearance.
The flowers are yellow with red centers.
Myriostigma
Commonly known as bishop’s hat, bishop’s cap, or bishop’s miter, A. myriostigma is one of the most widely cultivated of the astrophytums.
At maturity, plants reach four to 10 inches wide and up to two feet tall, though occasionally they can reach five feet tall at maturity.
Spineless plants are green with white flecks or may be smooth, without flocking.
This species produces three to 10 ribs, with areoles along the ribs, and bears flowers that are yellow with yellow centers.
There are many A. myriostigma cultivars available, including the fascinating ‘Kikko.’
‘Kikko’ has horizontal furrows in its ribs, giving the plants a unique texture.
There are different forms of the ‘Kikko’ cultivar, some of which are quite geometrical looking, while others look more like they were roughly sculpted out of clay by children!
Ornatum
With the most spines of all astrophytums, A. ornatum is most commonly known as monk’s hood cactus but is also sometimes called ornamented bishop’s cap.
Monk’s hood cactus is dark green to grayish green, and globe-shaped, becoming cylindrical as it matures. This species can reach 12 inches wide and six feet tall or more as it ages.
The skin is covered with white flecks, but in variable amounts – they can be very sparsely or quite densely covered, with the flecks creating beautiful patterns.
Monk’s hood cacti usually produce eight ribs, but this number can be between five and 10, giving the plant a star shape when viewed from above.
A. ornatum bears yellow flowers with yellow centers when it blooms.
The conservation status of monk’s hood cactus is vulnerable as a result of habitat destruction and overcollection, so shop responsibly or grow it from seed instead.
