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Bishop's Miter, Bishop's Cap, Mitra, Bonete de Obispo

Astrophytum myriostigma var. nudum

Family: Cactaceae (kak-TAY-see-ee) (Info)
Genus: Astrophytum (ass-troh-FY-tum) (Info)
Species: myriostigma var. nudum
Synonym:Astrophytum myriostigma var. nuda
Synonym:Astrophytum myriostigma f. nuda
Synonym:Astrophytum nuda
Synonym:Astrophytum myriostigma subsp. potosinum var. nudum


Cactus and Succulents

Foliage Color:

Unknown - Tell us

Bloom Characteristics:

Unknown - Tell us

Water Requirements:

Drought-tolerant; suitable for xeriscaping

Average Water Needs; Water regularly; do not overwater

Where to Grow:

Suitable for growing in containers


under 6 in. (15 cm)

6-12 in. (15-30 cm)


9-12 in. (22-30 cm)

12-15 in. (30-38 cm)


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:

Sun to Partial Shade

Light Shade



Bloom Color:

Pale Yellow

Bloom Time:

Mid Spring

Late Spring/Early Summer

Mid Summer


Unknown - Tell us

Other details:

Unknown - Tell us

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:


Propagation Methods:

From seed; sow indoors before last frost

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


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


Tucson, Arizona

Carlsbad, California

El Cajon, California

San Diego, California

Santee, California

Temecula, California

show all

Gardeners' Notes:


On Aug 5, 2008, Vida7 from San Diego, CA wrote:

Great Cacti plant all around....Very drought tolerant and can take an extreme hot beating from the sun and can stand cold frosty winters. Got mine 5 yrs ago here in San Diego and was the size of a golf ball. Now it is around the size of a medium sized softball. Can also water as much as you want and will not get root rot. It'll take as much water as you can give it.


On Mar 3, 2004, palmbob from Acton, CA (Zone 8b) wrote:

Normally a grey plant with a very rough almost sandy surface, the nudum variety has just 'normal' green cactus skin... though saw in Huntington gardens, Pasadena and an older plant has a more weathered look and harder to tell the difference. Has an almost shark-like skin. Bishop's hat spineless cactus. Flowers are light yellow