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Homalocephala polycephala

Homalocephala polycephala
Photo: Robb Hannawacker, while working for Joshua Tree National Park, Public domain

Homalocephala polycephala, the cotton top cactus, is a clustering barrel cactus from the Mojave and Sonoran deserts that forms clumps of up to 30 stems. It needs full sun, very sharp drainage and little water, and is best grown outdoors or in a large, gritty pot.

Family
Cactaceae (Cactus family)
Grows as
Succulent
Light
Full sun
Water
Water deeply but rarely, letting the soil dry out completely between waterings, and reduce or stop watering in winter.
Soil
Very fast-draining cactus or gritty mix, such as sand, pumice and loam.
Temperature
Tolerates heat well; protect from frost, generally below about -5 °C, and keep dry when cold.
How easy
Easy
Native range
S. California, S. Nevada, Arizona, Mexico (Baja California Sur, Sonora)
Climate
desert or dry shrubland

About

Homalocephala polycephala, synonym Echinocactus polycephalus, is a cactus that is native to the United States and Mexico.

Where it grows

It occurs in the Mojave Desert region of Arizona, California, and Nevada, and also occurs in the Sonoran Desert region of southern California and northern Sonora, Mexico, growing on rocky hills and slopes at elevations between 30 and 750 meters. The plants grow in some of the most extreme arid environments in the American Southwest, such as Death Valley National Park, and the Mojave National Preserve of Southern California.

Other Echinocactus plants

Cactus · Homalocephala parryi · Horse Crippler · Barrel Cactus

Text excerpted from the Wikipedia article Homalocephala polycephala by its contributors, under CC BY-SA 4.0; the excerpts and the care summary drawn from them are shared under the same licence.

The care summary was written by AI (Claude, Anthropic) from the sources on this page, with general growing knowledge where they are silent. Check before relying on it.

Life form, climate and native range: World Checklist of Vascular Plants, Royal Botanic Gardens, Kew (CC BY 3.0), reformatted; see Plants of the World Online.

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