Description
Description: The standard Ariocarpus retusus (f.ma furfuraceus) is a solitary, slow growing geophyte cactus with tubercles slightly projecting above ground level. The “major” form is a cultivated selection with very wide leaflike, divergent tubercles. In earlier times, these large tubercled A. retusus were called “Tama-botan” in Japan. Today, Tama Botan is a generic name for wide tubercled A. retusus.
Tubercles: The wide smooth tubercles, with flat surface are the main distinctive characteristic of this priced form, they are 3,5 to 5 cm wide, and are as wide as long or wider in adult specimens.
Stem: Grey, or blue-green, flattened, globose, rounded on top, 3-12cm high, 20-30 cm in diameter.
Flowers: Diurnal 4-5cm in diameter., 2-4 2cm long; white to pink, occasionally with reddish midribs,
Root: Tap root
Flowering time: October
Fruit: White, green, or rarely pinkish, 10-25mm long, 3-10mm in diameter.
Remarks: Ariocarpus retusus is an extremely variable species,. Tubercle size and shape vary widely, a terminal areole is sometimes present at the tip. The vast amount of phenotypic variation in the species has led to the erection of several variants:
Origin and Habitat
Garden origin (Nursery produced cultivar) Japan.
Cultivation and Propagation
This species is slow growing but certainly not as slow as some other types of cacti, it is of easy culture in a well drained, non-organic, free-draining soil compost, with ample water during the growing season. Use of a weak low-nitrogen fertilizer during the growing season can encourage growth. The main threat to their development is root rot. Ariocarpus should be kept dry whenever there is a threat of cold. The appearance of Ariocarpus can benefit greatly by watering the plants from the bottom. This practice will help to keep the “wool” on the top of the plant from becoming matted or discoloured. Need light shade to full sun. Frost Tolerance: Hardy to -10° C
Propagation: It is probably the easiest species of the genus to raise from seed, but will generally take about 6-10 years to reach flowering size, occasionally grafted.