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

Astrophytum myriostigma

Family: Cactaceae (kak-TAY-see-ee) (Info)
Genus: Astrophytum (ass-troh-FY-tum) (Info)
Species: myriostigma (my-ree-oh-STIG-muh) (Info)
Synonym:Astrophytum myriostigma var. myriostigma
Synonym:Echinocactus myriostigma
Synonym:Astrophytum prismaticum


Cactus and Succulents

Foliage Color:


Bloom Characteristics:

Unknown - Tell us

Water Requirements:

Drought-tolerant; suitable for xeriscaping

Average Water Needs; Water regularly; do not overwater

Where to Grow:

This plant is suitable for growing indoors


under 6 in. (15 cm)

6-12 in. (15-30 cm)


6-9 in. (15-22 cm)

9-12 in. (22-30 cm)

12-15 in. (30-38 cm)

15-18 in. (38-45 cm)


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)

Sun Exposure:

Full Sun

Sun to Partial Shade

Light Shade



Bloom Color:

Pale Yellow

Bright Yellow

Bloom Time:

Mid Summer

Late Summer/Early Fall

Mid Fall




Other details:

This plant may be considered a protected species; check before digging or gathering seeds

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; winter sow in vented containers, coldframe or unheated greenhouse

From seed; sow indoors before last frost

From seed; direct sow after last frost

Seed Collecting:

Collect seedhead/pod when flowers fade; allow to dry

Allow unblemished fruit to ripen; clean and dry seeds

Properly cleaned, seed can be successfully stored


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


Chandler, Arizona

Gold Canyon, Arizona

Maricopa, Arizona

Phoenix, Arizona

Scottsdale, Arizona

Tucson, Arizona (2 reports)

Brea, California

Carlsbad, California

Castro Valley, California

Perris, California

Reseda, California

San Diego, California

Palacios, Texas

show all

Gardeners' Notes:


On Oct 15, 2011, Bronto from Scottsdale, AZ wrote:

The Bishop's cap cactus seems virtually indestructible in a pot indoors, or outside in soil or pot with good drainage in warm/desert climate. A great plant for novice cactus enthusiast, will survive well indoors in sunny window, leave mostly dry in cold weather. A potted specimen moved from LA to a pot in Alaska, into the ground in Arizona, and then into a pot again has survived for over 25 years, and is now 18" in height. It has not been repotted in 10 years.


On Mar 18, 2008, palmbob from Acton, CA (Zone 8b) wrote:

In my garden this is one of the easiest and hardiest cactus to my forms of abuse I own. I have about 10 of these now, and they survive all sorts of random watering strategies, bright, searing hot, full day sun (got to 120F few years ago and didn't affect these), and down to 25F with no damage... and some live in almost total shade (no direct sunlight at all) and do fine. All live outdoors and get drenched all winter long by our cold rains here in southern California, and to no ill effects whatsoever (though most cacti tolerate our freezing cold rains for some reason despite everyone's recommendations to keep them dry in winter). Never had one of these rot. The move easily, have no spines, look great all year round in any condition... just about one of the most perfect cacti you can gro... read more


On Nov 4, 2005, cactus_lover from FSD
Pakistan (Zone 10b) wrote:

Many varieties/forms discribed for this species including the columnar V,columnare.Tsuda,the four ribbed V, quadricostatum.Baum and the flock-less V,nudum.


On Aug 31, 2003, Happenstance from Northern California, CA wrote:

Easy to grow cactus, flowers readily, most used common name is Bishops's Cap. Was Echincactus myrostigma.


On Nov 30, 2002, philomel from Castelnau RB Pyrenes
France (Zone 8a) wrote:

This plant has showy yellow flowers between June and September. However, the rest of the year it gives pleasure from its interesting form and texture.

It should be kept dry over winter.