Scientific Name
Ariocarpus trigonus (F.A.C.Weber) K.Schum.
Common Name(s)
Living Rock, Star Rock
Synonym(s)
Anhalonium trigonum, Ariocarpus retusus subsp. trigonus, Ariocarpus trigonus var. minor
Scientific Classification
Family: Cactaceae
Subfamily: Cactoideae
Tribe: Cacteae
Genus: Ariocarpus
Origin
Ariocarpus trigonus is native to Mexico. It grows in rocky limestone areas at elevations ranging from 1,970 to 3,940 feet (600 to 1,200 m) in Tamaulipas and Nuevo Leon.
Description
Ariocarpus trigonus, also known as Ariocarpus retusus subsp. trigonus is a slow-growing geophytic cactus with a solitary, yellowish-green stem covered with long, stiff tubercles with wooly bases, resembling a rosette. It is one of the largest species in the genus. The stem is spherical, more or less depressed, and can grow up to 10 inches (25 cm) tall and 12 inches (30 cm) in diameter.
The flowers are cream-colored to yellowish-white or yellow, occasionally with reddish midribs, and appear from late fall to early winter. They can reach up to 1.8 inches (4 cm) in length and 2 inches (5 cm) in diameter. The fruits are whitish or greenish, measuring up to 0.8 inches (2 cm) long and 0.4 inches (1 cm) in diameter.
Hardiness
USDA hardiness zones 9b to 11b: from 25 °F (−3.9 °C) to 50 °F (+10 °C).
How to Grow and Care
Plant your Ariocarpus in soil specifically formulated for cacti. You can buy a cactus mix at your local nursery. Do not use generic soil mixes because they will not provide enough aeration and drainage. Additionally, using a container without a hole, whether a pot or a terrarium, is a bad idea for the same reason.
Ariocarpus need a lot of sunlight. However, in hot, dry areas, they can be damaged by excessive sunlight, so you should use a shade cloth to limit their sun or move them out of the sun during the hottest hours of the day. In more temperate areas, direct sunlight is fine.
These cacti prefer to be kept at room temperature or slightly lower and in low humidity.
Water your Ariocarpus when it is dry, but wait until the soil dries out completely to water it again. The amount of time this takes will vary depending on your climate and the size of your pot if you use one.
Learn more at How to Grow and Care for Ariocarpus.
Links
- Back to genus Ariocarpus
- Succupedia: Browse succulents by Scientific Name, Common Name, Genus, Family, USDA Hardiness Zone, Origin, or cacti by Genus
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