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ASTROPHYTUM myriostigma

Image of Astrophytum myriostigma

James H. Schutte



Botanical Name

ASTROPHYTUM myriostigma

Plant Common Name

Bishop's Cap, Star Cactus

Special Notice

This entry has yet to be reviewed and approved by L2G editors.

General Description

Bishop’s cap is an ideal windowsill cactus because it is thankfully spineless or nearly so. This tiny, rock hard gem of a plant does not demand high intensity light and will thrive in any south facing exposure as a house plant. It is native to the Chihuahuan Desert of central Mexico, but has been in cultivation so long there are numerous horticultural varieties. What makes it so unique is that each plant is a perfect five pointed star divided into as many identical segments. Bishop’s cap protects itself with a dense layer of fine chalky scales that give it a silvery gray color overall. Handle this cactus with care since the fragile scales can be easily rubbed off and will not grow back.

Bishop’s cap is a spring blooming species. At the center of the plant buds form at the tubercles that line the ridge that bisects each segment. These open into numerous vivid yellow flowers, each the size of a quarter. They are long lasting, drop off cleanly and rarely form seed capsules. Collectors of Astrophytum often seek out individuals with just four or six sections, which is not uncommon, giving these unique forms a higher commercial value.

Like other star cactus, bishop’s cap does not ask for much water and thrives even with a very small, Spartan root zone. They demand fast drainage overall and are downright hard to kill except with excessive moisture and rich soils. Very slow growth and small size is what makes them ideal for bonsai pots and other creative containers on porch, window sill or balcony. This is an ideal choice for beginners due to its lack of thorns, exceptional geometry and ease of cultivation indoors.


  • AHS Heat Zone

    12 - 10

  • USDA Hardiness Zone

    12 - 15

  • Sunset Zone

    21, 22, 23, 24

  • Plant Type

    Cactus or Succulent

  • Width

    8"-12" / 20.3cm - 30.5cm

  • Bloom Time


Growing Conditions

  • Growth Rate

    Very Slow

  • Water Requirements

    Xeric/Desert, Drought Tolerant

  • Habit


Ornamental Features

  • Flower Color


  • Fruit Color


  • Flower Petal Number


  • Showy Fruit


  • Edible Fruit


Special Characteristics

  • Attracts