Mammillaria nunezii

Mammillaria nunezii is a small cactus in the Cactaceae family. It comes from central and southwestern Mexico. Its range includes Guerrero, Morelos, Jalisco and Michoacan. It grows in oak woods in a seasonally dry tropical climate. Wild plants occur at 3,280–5,250 feet [1,000–1,600 metres] above sea level. Some sites hold many plants, while others hold few. Farming threatens parts of its habitat. People in its native range grow it for ornament.

This slow-growing cactus forms a single stem or, less often, clusters. Stems reach about 0.5 feet [0.15 metres] tall. Each measures 0.2–0.3 feet [0.06–0.09 metres] across. They range from round to upright and cylindrical. Their pale green or grey-green tops have a sunken centre. The stems lack latex, and the roots are fibrous. Close-set tubercles have cone-shaped or blunt, four-angled forms. Silky bristles and some wool grow between them.

Large areoles carry white wool and a dense coat of spines. Each has 10–30 thin, stiff, white radial spines. These spread outward, with the shortest ones at the top. Most measure 0.016–0.023 feet [0.005–0.007 metres] long. The central spines differ in length and number. Most are straight, though one may form a hook. They are brown or reddish brown, with dark tips. There are usually two to four, but sometimes nine.

Deep pink to magenta flowers appear in early summer, including June. Their funnel-shaped blooms open only a little and have green stigma lobes. Flowers span 0.039–0.049 feet [0.012–0.015 metres]. The club-shaped fruits look greenish white with a pink tint. They reach about 0.082 feet [0.025 metres] long. Fruit takes 12–14 months to ripen after flowering. Small brown seeds range from round to club-shaped.

LLIFLE describes this species as easy to grow. Use a very porous potting mix and a pot that drains well. Water through summer, but avoid excess water because it can cause rot. Keep the plant dry through winter. A summer feed should contain plenty of potassium. Strong light helps it flower and form good spines. Sudden moves from shade to full sun can scorch it. Dry plants reportedly withstand temperatures down to 23°F [−5°C].