Coryphantha
Coryphantha retusa

Family: Cactaceae (kak-TAY-see-ee) (Info)
Genus: Coryphantha (kor-ry-FAN-tha) (Info)
Species: retusa (re-TOO-suh) (Info)
Synonym:Coryphantha retusa var. retusa
Synonym:Mammillaria cephalophora
Synonym:Echinocactus cephalophorus
Synonym:Melocactus mammillariaeformis
Synonym:Cactus cephalophorus

Category:

Cactus and Succulents

Height:

under 6 in. (15 cm)

Spacing:

6-9 in. (15-22 cm)

9-12 in. (22-30 cm)

12-15 in. (30-38 cm)

Hardiness:

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)

Sun Exposure:

Full Sun

Sun to Partial Shade

Light Shade

Danger:

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

Bloom Color:

Orange

Red-Orange

Pale Yellow

Bright Yellow

Bloom Time:

Late Summer/Early Fall

Foliage:

Succulent

Other details:

Drought-tolerant; suitable for xeriscaping

Average Water Needs; Water regularly; do not overwater

Suitable for growing in containers

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 woody stem cuttings

Allow cut surface to callous over before planting

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

Regional

This plant has been said to grow in the following regions:

Phoenix, Arizona

Gardeners' Notes:

1
positive
2
neutrals
0
negatives
RatingContent
Neutral

On Aug 19, 2008, CactusJordi from El Cajon, CA wrote:

According to literature this species is NOT offsetting and only very rarely has 1 central spine (typically none)

Jordi

Positive

On Sep 12, 2004, TucsonJen from Tucson, AZ (Zone 9a) wrote:

I just happened to be in line behind a couple who were buying one of these yesterday. It was a cluster of about 5 with the large central one in bloom. It looked great! The store employees disagreed as to whether or not it clustered frequently.

Neutral

On Sep 12, 2004, Xenomorf from Valley of the Sun, AZ (Zone 9b) wrote:

Another synonym of Coryphantha retusa is Cactus cephalophorus.