cactus with abundant white wool on top.
Stem: Subglobose to elongate, up to 15 cm in diameter. The
“viridis” form has a slate blue or green body (whereas the standard form
generally has a grey-purple tinged stem).
Root: Conical taproot.
Adult specimens have around
8-13 notched ribs, forming tubercles with sunken areoles.
Spines: Juvenile specimens have 1 central
spine and 8 radials, but the numbers increase as they get older, and
areoles can have over 20 spines on mature specimens.
Central spines: Dark brown to black, soon becoming chalky-white or
greyish, up to 20 mm long.
Radial spines: 6-12, up to 1 cm long.
Flowers: From young areoles,
campanulate or funnel-shaped, very pale
pink, cream-white or pale yellowish with a vague green nuance. About 3
cm in diameter. Floral tube with abundant white wool and bristles.
There might be over 50 flowers on a mature specimen (only mature
Fruit: Reddish, elongate, opening by a basal pore.
It is a
summer-growing species. It's easy to cultivate, but somewhat
rot prone if kept in a non
ventilated place. It requires a very fast-draining, drying soil.
Water regularly in summer, but do not over-water.
It needs a
full sun exposure (or
light shade). Good heat tolerance.
Hardy to at least -5°C.
Usually propagated from Seeds.
(seldom produces offsets)
conspecific taxa, varieties, forms and cultivars
of plants belonging to the
Taxon is very variable taxon with a
endless list of synonyms, with
several controversial varieties and subspecies,
and comprises a multitude of different forms, but where each form is
linked to others by populations of plants with intermediate