Mammillaria Celsiana is a massive globose cactus with bright carmine flowers. It is solitary when young, but each single stem begins to divide dichotomously to form two stems as it matures, this process repeats several times giving rise to small clustered groups and occasionally to large mounds with dozen of heads. Seen from above the central whorl of woolly areoles resembles a sunflower head.
Stems: Individual stems globose, becoming cylindric with age, 10-15 cm tall (or more), 7-15 cm in diameter, apex somewhat sunken and woolly, dark green, blue-green or grey-green.
Tubercles: Conical to pyramidal-shaped, compact, without latex.
Axil: Woolly and with white bristles.
Tubercles arrangement: 13-21.
Areoles: Small, round, woolly when young.
Radial spines: 24 to 50, about equal up to 4 mm long, glassy white or yellowish, bristle-like, radiating, nearly covering the body.
Central spines: Usually 4, rarely 2 to 7, somewhat longer than the radials, terete, rigid, pale yellow, more or less recurred pointing outward, and markedly unequal, 2 to 40 mm long, lowermost
longest, brownish yellow, becoming grey with brown tips.
Flowers: Small in a ring near the top of the cactus on previous years growth, 10-15 mm long, bright carmine to rose-red with reddish-brown outer petals.
Blooming season: Summer.
Cultivation and Propagation: Mammillaria muehlenpfordtii is not particularly difficult on own roots. No special cultural requirements.
Growth rate: It is an easily flowering species and a relatively rapid grower in comparison to other spherical species, the plant will increase the number of heads by dichotomous division. Large clumps can be produced in a few years given the best conditions.
Soils: It likes very porous standard neutral or slightly alkaline cactus mix soil.
Repotting: Use pot with good drainage.