Common Name: bishop's hat
Type: Herbaceous perennial
Family: Cactaceae
Native Range: Northeastern Mexico
Zone: 7
Height: 0.25 to 2.00 feet
Spread: 0.25 to 0.75 feet
Bloom Time: Seasonal bloomer
Bloom Description: Creamy white to pale yellow
Sun: Full sun
Water: Dry
Maintenance: Low
Flower: Showy, Fragrant
Tolerate: Dry Soil, Shallow-Rocky Soil
Culture
Best grown in dry, sandy, fast-draining soil in full sun. Hardy in frost free Zones 10-11.
Noteworthy Characteristics
Astrophytum myriostigma, commonly called bishop's hat or bishop's cap cactus, is a spinless cactus native to rocky, calcareous soils of the northern and central Mexican uplands at elevations from 2500-5000' above sea level. The rounded to oval shaped plants are unbranched and typically have five (rarely four and up to eight) broad, prominent ribs which narrow to an acute point. The ribs are covered in small, densely woolly patches, giving the plant its characteristic grey-green appearance. Mature plants will reach up to 2' tall and 8" wide. The number of ribs tends to increase with age. The funnel-shaped, fragrant flowers range in color from creamy white to pale yellow and reach around 2" long with an equal width. Bloom time is somewhat sporadic in cultivation, but typically occurs in spring or summer.
Genus name comes from the Greek words astron meaning a star and phyton meaning a plant in reference to the low, spreading star-like habit.
The specific epithet myriostigma comes from the Greek myrios meaning "many" and stigma meaning "point", in reference to the abundance of small, woolly scales covering the ribs of this species.
The common names for this species refer to the similarities of its shape to the mitre hat worn by bishops in certain sects of Christianity.
Problems
Scale and mealy bugs can be problematic, particularly because they may blend in to the woolly scales covering the ribs of this plant. Root rot is caused by overly moist soils.
Uses
Houseplant, desert gardens.