The needs of an Astrophytum cactus are the same as for other cacti—coarse, porous soil, and plenty of sunlight. While this cactus can be grown as a landscape garden specimen in the proper climate, it more commonly is used as a potted specimen for indoor growing or on decks and patios.
Astrophytums are not vigorous plants, and they require a lot of patience to reach their full potential. Keep regularly watering and feeding them during the growing season and repot annually to give them space to develop. They need a temperate, dry winter; make sure not to overwater them, which can cause root rot. If given sufficient care, they will develop marvelous flowers once they reach maturity.
Give Astrophytum cacti plenty of sunlight—at least 6 hours per day if growing outdoors. As a potted indoor plant, it can do fine in a window that gets direct sunlight or intense indirect light.