Mammillaria muehlenpfordtii
| Light | Bright light; a little shade from the fiercest afternoon sun |
|---|---|
| Water | Sparingly; allow to dry fully between waterings, dry rest in winter |
| Soil | Fast-draining mineral mix (see Soil and potting mix) |
| Temperature | Keep above freezing; USDA zones 9b–11 |
| Propagation | Seed (primary); division of clumping heads |
| Toxicity | Non-toxic to cats and dogs |
Mammillaria muehlenpfordtii is a robust, globular pincushion cactus from central Mexico, solitary-headed when young but dividing at the growing tip with age to build into a multi-headed clump, prized for its handsome spination and white crown wool. Its firm green body carries stout yellow, brown-tipped spines and tufts of white wool and bristles toward the crown, and in season it rings its apex with small carmine flowers. It is grown widely as an easy, undemanding member of the genus Mammillaria.
Description
Mammillaria muehlenpfordtii forms a solid green globe that is solitary when young but divides at the growing tip with age, so that older plants carry several heads and gradually mound up into a clump, reaching a fair size for the genus. The firm, deep green body is packed with conical tubercles; white wool and bristles gather in the axils and at the young areoles, especially toward the crown, giving the growing tip a clean, frosted look, though this wool tends to diminish as the plant ages.
Each areole bears numerous fine, pale radial spines (white to yellowish) and usually about four longer, stouter central spines. The centrals are yellow to brownish-yellow, typically with darker brown tips, and the lowest is elongated and curves downward, giving the plant a characteristic downswept look. In summer and autumn the plant produces partial rings of small, funnel-shaped carmine-red flowers around the crown, followed by the slender red fruits typical of the genus.
Distribution and habitat
The species is native to central Mexico — the states of San Luis Potosí, Guanajuato and Querétaro — where it grows on rocky slopes and in dry scrub at roughly 1,700–2,400 m elevation, among grasses and low shrubs. As with most Mammillaria, it favours gritty, well-drained ground and full or nearly full sun, enduring long dry spells punctuated by seasonal rains.
Like the whole cactus family, it is listed under CITES Appendix II, but nursery-propagated plants are common, inexpensive and entirely legal to own and trade.
Cultivation
Mammillaria muehlenpfordtii is one of the more forgiving pincushion cacti and a good choice for a keen beginner. Grow it in a very free-draining, mostly mineral mix in bright light with a little shade from the harshest afternoon sun, which brings out the best spine colour and keeps the body compact. Water thoroughly once the soil has dried right through, then wait; taper off in autumn and keep the plant cool and dry over winter to encourage flowering and to prevent rot.
Its dense crown wool can trap moisture, so water at the soil rather than over the top of the plant, and give it good air movement. See Watering and Repotting for general technique.
Propagation
Seed is the usual and most reliable method: sown on a warm, moist mineral surface, the seed germinates readily and seedlings grow at a reasonable pace for the genus. Rather than throwing ordinary basal offsets, this species multiplies by dividing at the growing tip, so an older clump can sometimes be split and a separated head callused and rooted as with other clustering cacti — see Propagation — offsets and Propagation — seed for full walkthroughs.
Common problems
- Rot — almost always from overwatering or a slow-draining mix; the body softens and browns, often starting from the base.
- Etiolation — too little light makes the body pale and stretched and the spines weak.
- Pests — mealybugs love to hide in the axillary wool (white fluff, sticky residue), and red spider mites can bronze the skin in hot, dry, stagnant air. See Pests and diseases.
See also
- Mammillaria — the genus overview
- Soil and potting mix · Watering · Propagation — seed · Propagation — offsets · Repotting