Astrophytum myr. nudum 'quadricostatum' 14cm
Astrophytum myriostigma var. nudum (Rud.Mey.) Megata
Description: Astrophytum myriostigma var. nudum (nude form also known as “Hekiran” in Japanese speech) is very similar to the other myriostigma, it only deviate from the well-known typical form for lacking or mostly lacking white flecks, giving a bright green, blue-green, gray-green or mauve-green color overall depending on clones.
It is by some considered an extreme form of the subspecies potosinus.
Cultivation and Propagation: Astrophytum myriostigma is a summer grower species relatively easy to grow. It is sometime seen as a grafted plant but grows very well on its own roots too.
Growth rate: It is a slow growing and easily flowering species.
Soil: Use mineral well permeable substratum with little organic matter (peat, humus), plants may become too elongated if compost is too rich.
Repotting: Re-pot every 2 years. Use pot with good drainage.
Fertilization: It grows much faster with a low nitrogen content fertilizer in spring and summer. Potassium helps maintaining the plants compact and healthy.
Watering: Requires careful watering to keep plant compact. Water sparingly from March till October, the thin, fibrous roots suffer if there is humidity, therefore the plant should be watered only when the surrounding terrain is dry. Keep dry as soon as the temperature starts dropping in October and keep it perfectly dry in winter at temperatures from 5 to 15 degrees centigrade.
Hardiness: They need to be kept in a cool place during winter rest and are somewhat resistant to frost if kept on the dry side prior to, and during, cold weather (due to the altitude they are hardy to -5 C ° C, or less for short periods). Although it is one of the easier Astrophytum to grow, it tends to rot in winter during the resting phase, if kept wet. In the rest period no high atmospheric humidity!!
Sun Exposure: Light shade to full sun, its colour tends to richer and darker when grown in light shade.
Uses: It is an excellent plant for container growing. It always looks good and stays small.