Star Plant, Monk's Hood

Astrophytum ornatum

Family: Cactaceae (kak-TAY-see-ee) (Info)
Genus: Astrophytum (ass-troh-FY-tum) (Info)
Species: ornatum (or-NAH-tum) (Info)
Synonym:Astrophytum ornatum var. ornatum


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:

Unknown - Tell us


12-18 in. (30-45 cm)


6-9 in. (15-22 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)

Sun Exposure:

Sun to Partial Shade


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

Bloom Color:

Bright Yellow

Bloom Time:

Mid Spring

Late Spring/Early Summer

Mid Summer

Late Summer/Early Fall



Other details:

Unknown - Tell us

Soil pH requirements:

5.1 to 5.5 (strongly acidic)

5.6 to 6.0 (acidic)

Patent Information:


Propagation Methods:

From woody stem cuttings

Allow cut surface to callous over before planting

From seed; sow indoors before last frost

From seed; direct sow after last frost

From seed; germinate in vitro in gelatin, agar or other medium

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:


Phoenix, Arizona

Tucson, Arizona

Bostonia, California

Fontana, California

Thousand Oaks, California

Kermit, Texas

show all

Gardeners' Notes:


On Jul 23, 2007, franj from Tucson, AZ wrote:

In my experience at least, one of the easiest Astrophytums to grow. They will flower prolifically throughout the spring and summer. I have one one in my garden that was baseball sized when planted a decade ago. I pretty much stuck it in the ground and left it to nature. It's now over 14 inches tall and 8 inches across. Grown in some shade it has unfortunately lost most of its flecking.

The pot grown specimen has been grown in full sun and maintained its flecking beautifully. This suggests to me that these plants appreciate the highest level of light you can give them to maintain the beauty and form of the plant. Howhever both plants seem to flower often producing outstanding displays of 2 inch wide flowers.

Fruits are as spiny as the flower bud, nestled down... read more


On Jul 28, 2005, leeann6 from Kermit, TX (Zone 7b) wrote:

This cactus is pretty cold hardy,,, it survived 10F for 4 days and nights. Covered it with a black plastic pot.. was real surprised! I just love it!


On Sep 19, 2003, palmbob from Acton, CA (Zone 8b) wrote:

Though usually grown in pots as odd and attractive specimens, this plant and most of the other Astrophytums have done well in my old cactus garden in So Cal. Some develop nice twists with age.