hairspine prickly pear

Photo: Matt Lavin from Bozeman, Montana, USA — CC BY-SA 2.0 · source

Survives zone 3 through 9

Harvest calendar

Best planted in early spring after your last frost, or in fall before the ground freezes, depending on your climate.

One of the most cold-hardy and widely distributed Opuntia in North America, ranging from Chihuahua, Mexico north through the Great Plains and Rocky Mountain states into Alberta and Saskatchewan, with a disjunct population found in Ontario's Thousand Islands in 2018 — it is one of only two cactus species native to Canada. ⚠ Glochids.

Hardiness

Zone 3–9

Habit

Groundcover

Edible part

Seed, Fruit

Ripens

Late summer–autumn

Mature size

Low mats 10–30 cm tall, spreading 1–2 m; excellent in containers

Light

Full sun (open-ground desert/glade)

Soil pH

6.5–8.0 (neutral–alkaline, sharp drainage)

Environment

Temperate

Native range

Chihuahua in northern Mexico north through Arizona, Utah, the Rocky Mountain states and the Great Plains to Alberta and Saskatchewan, and west to Nevada and California — the most widespread cactus in the United States. British Columbia's prickly pears were long reported as this species, but the province now refers them to O. fragilis and the hybrid O. × columbiana; Ontario's are O. fragilis and, at Point Pelee, O. humifusa.

Status

Wild

Years to fruit

2–3 yrs

Growth speed

Slow to moderate — a few new pads a season once established

Spacing

250 cm (98 in) apart — about 6.3 m² (67 sq ft) per plant

Leaf shape

Succulent, oval-to-round green pads up to about 27 by 18 cm (10.6 by 7.1 in), with areoles tipped in woolly brown fibers and glochids, and spines highly variable in length (0.4–18.5 cm) and form.

Root system

Shallow and fibrous, with most of the root mass in the top 15 cm and spreading as far as 2.5 m from the plant within two seasons — a mat built to catch light rain before it evaporates rather than to reach deep water. It needs no soil depth, but it does need sharp drainage: standing wet in winter kills far more plants than cold does.

Fruit description

Cylindrical, tan-to-brown, dry and spiny fruit, roughly 15–45 mm long and 12–25 mm in diameter at maturity.

Propagation

Propagated from pad cuttings, calloused before rooting in very sharply drained, gritty soil.

Pollination

Self-fertile

The edible parts listed above are a starting point, not a field guide. Identify a plant with certainty — ideally against a local authority — before eating any part of it, and read the full disclaimer. Spotted something wrong? Report it.