Astrophytum myriostigma “quadricostatum” var. nudum
Astrophytum myriostigma cv. quadricostatum nudum
A. myriostigma “quadricostatum” nudum grows a quadrangular to spherical stem, characterised by the presence of four ribs instead of five. Aging, the plant can get shortly columnar-shaped, getting up to 90 cm tall. The glabrous stem lacks totally or mostly the white flecks typical of this cultivar, showing the bright/blue-green epidermis. After 6 years of live, this Astrophytum may bloom in warm seasons, with pale-yellow, silk-shining flowers arising on the stem top, from the areole.
This Astrophytum is a quite slow-growing cultivar. It needs a mineral, well-draining substratum, and a good amount of sunlight to grow faster. Water it sparingly from spring to autumn, and during sunny and warm weather you can add a little fertilizer. Theoretically, A. myriostigma quadricostatum is tolerant to freezing temperatures (-7°C), but during winter it needs to be kept perfectly dry to avoid root rot and frost damages.
Even if you can find this Astrophytum grafted on other cacti, usually propagation is done by seeds.
The original description of this Astrophytum dates back to 1839.