Sea Urchin Cactus, Cory-Cactus Hedgehog, Prickly Beehive Cactus
Coryphanthaechinus

Synonym:Coryphantha radians var. echinus

Synonym:Coryphantha cornifera var. echinus

Synonym:Coryphantha pectinata

Synonym:Mammillaria radians var. echinus

Synonym:Mammillaria echinus

Category
Cactus and Succulents

Water Requirements
Drought-tolerant; suitable for xeriscaping
Average Water Needs; Water regularly; do not overwater

Sun Exposure
Full Sun
Sun to Partial Shade

Foliage

Foliage Color

Height
under 6 in. (15 cm)

Spacing
3-6 in. (7-15 cm)
6-9 in. (15-22 cm)
9-12 in. (22-30 cm)

Hardiness
USDA Zone 6a: to -23.3 °C (-10 °F)
USDA Zone 6b: to -20.5 °C (-5 °F)
USDA Zone 7a: to -17.7 °C (0 °F)
USDA Zone 7b: to -14.9 °C (5 °F)
USDA Zone 8a: to -12.2 °C (10 °F)
USDA Zone 8b: to -9.4 °C (15 °F)
USDA Zone 9a: to -6.6 °C (20 °F)
USDA Zone 9b: to -3.8 °C (25 °F)
USDA Zone 10a: to -1.1 °C (30 °F)
USDA Zone 10b: to 1.7 °C (35 °F)
USDA Zone 11: above 4.5 °C (40 °F)

Where to Grow
Can be grown as an annual

Danger
Plant has spines or sharp edges; use extreme caution when handling

Bloom Color
Bright Yellow

Bloom Characteristics

Bloom Size

Bloom Time
Late Spring/Early Summer

Other details

Soil pH requirements
6.1 to 6.5 (mildly acidic)
6.6 to 7.5 (neutral)
7.6 to 7.8 (mildly alkaline)

Patent Information
Non-patented

Propagation Methods
From seed; direct sow after last frost

Seed Collecting
Allow unblemished fruit to ripen; clean and dry seeds
Unblemished fruit must be significantly overripe before harvesting seed; clean and dry seeds
Properly cleaned, seed can be successfully stored