Origin and Habitat: Garden origin (Nursery produced cultivar)

• Mammillaria luethyi f. aurata hort.

• Mammillaria luethyi G.S.Hinton
• Mammillaria luethyi f. aurata hort.
• Mammillaria luethyi f. monstruosa hort.

Description: Mammillaria luethyiSN|26146]]SN|11876]] is a very tiny plant, but by far one of the most spectacular members of its genus, distinctive when not in flower because of the 'spination' (if it can be called that!) at the tips of the tubercles, and even more magnificent in flower. It is solitary or branching in several stems, mostly beneath the ground.
Forma aurea or aurata (yellow form): The schizochromic form (Mammillaria luethyi f. aurataSN|11876]]SN|26146]]) has pale yellow stems due to the absence (or reduced production) of chlorophyll pigments: every other pigment is present at normal levels, the dominant green colouration is lost, but will still more than likely have normal other pigments that give the yellow overall appearance of the stem. This form with yellow stems is very attractive and highly prized. This schizochromic form is almost always seen grafted on stronger columnar species, and cannot can be grown on its own roots. However some clones have enough chlorophyll in their tissues and can be grown on they own roots too, but very slow growing.
Growth Habits: Solitary or clustering.
Stem: 1.5 cm in diameter (Up to 4 cm in cultivation), flattened sub-globose, very dark-green almost black.
Tubercle: Dense, erect, slender, cylindrical. The axil is slightly bristly.
Spines: Short, minuscule, as many as 80, soft and white, not prickly, in several series, erect to radiating, forming a dense, flattened cluster 1-2 mm in diameter
Roots: Fleshy tap root, largely exceeding the dimension of the tiny stems.
Flowers: Large, 15-25 cm wide and long, rich magenta with a white throat.
Fruits: 4 to 5 mm in diameter, sunken in the stem, globose, yellow-green to reddish-green.
Seeds: Black.

Cultivation and Propagation: Variegated and albinos cacti are regarded as choice and difficult in cultivation, but despite that many of them are relatively easy to grow. But be aware that they cannot tolerate prolonged exposure to direct sun light (especially during the hottest summer days), so grow them in half-shade or under filtered sun. They are sometime seen as grafted plants, but many grow well on their own roots, too.
On the contrary, the albinos can survive only if grafted on a strong green base.
Use mineral well-permeable substratum with little organic matter (peat, humus). Water sparingly from March till October and keep perfectly dry in winter at temperatures from 5 to 15 degrees centigrade. (In general these plants are more tender and cannot endure freezing temperatures ) In the rest period no high atmospheric humidity!!
Propagation: Usually by seed. Plants are often grafted onto column-shaped cacti.