Cactus · Sonoran native
Arizona Fishhook Pincushion
Mammillaria grahamii · Cactaceae
Also called: Graham's Nipple Cactus, Fishhook Pincushion, Graham Fishhook Cactus, Sunset Cactus, Mammillaria microcarpa (synonym)
Arizona Fishhook Pincushion (Mammillaria grahamii) is a very low-water cactus native to the Sonoran Desert region well suited to Tucson and the low desert. It thrives in full sun to part shade, with a slow growth rate.
Arizona Fishhook Pincushion at a glance
- Water use
- Very Low (established)
- Sun
- Full sun to part shade; in nature often grows protected beneath nurse shrubs, and light afternoon shade is fine in Tucson.
- Mature size
- 2-6 in H x 2-3 in W (small; solitary or forming small clusters of a few stems)
- Growth rate
- Slow
- Bloom
- Pink to lavender-pink with darker midstripes (a crown of nearly 1-in flowers just below the stem tips), Summer (often May-September), characteristically opening within days of a soaking monsoon rain; may flower in flushes.
- Cold hardiness
- Hardy to about 10-15 F (USDA zones 9-11); thrives in low-desert heat.
- Soil
- Well-drained gravelly, sandy, or rocky native desert soil. Tolerates lean soils; will rot in heavy or poorly drained ground.
- Native range
- Arizona south of the Mogollon Rim, southern New Mexico, west Texas, and Sonora/Chihuahua, Mexico; abundant in the Sonoran Desert around Tucson in desert scrub, grassland, and rocky bajadas, often nestled under shrubs.
- Best used as
- Miniature accent in rock and cactus gardens, Container and dish gardens, Naturalistic 'under nurse plant' desert plantings, Pollinator gardens, Crevice and gravel-mulch plantings
- Wildlife
- Flowers attract native bees and other small pollinators; the bright red, fleshy, chili-shaped fruits are eaten by birds, rodents, and were a traditional human food.
- Toxicity
- Non-toxic; fruit is edible. Caution: the central spine is sharply hooked (fishhook) and can snag skin and clothing.
How to grow Arizona Fishhook Pincushion in Tucson & the low desert
Watering
Essentially rainfall-dependent once established; the summer monsoon triggers bloom. Supplemental water only in prolonged drought, and keep dry in winter to prevent rot.
Fertilizer & nutrients
None needed in native soil. An optional very dilute low-nitrogen cactus fertilizer once in late spring is more than enough.
Pruning & care
No pruning. Remove dead or rotted stems cleanly if they occur.
Notes
Long known as Mammillaria microcarpa; M. grahamii is the accepted name. The hooked central spine is diagnostic. Easy, cold- and heat-tolerant little native that blooms reliably after monsoon rains, earning the nickname 'flower-crown cactus.' Use nursery-grown plants.
Sources: Arizona-Sonora Desert Museum; University of Arizona Cooperative Extension; Sky Island Alliance; SouthwestDesertFlora.com