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You’ll Be Starstruck by the Bishop’s Cap Unique Shape

The Bishop’s Cap cactus is a slow-growing cacti native to northern and central Mexico as well as the southern United States. Astrophytum myriostigma , also known as the Bishop’s Hat, is an easy-to-grow houseplant making it great for beginners. The cactus has no spines, just like the Lamb’s Tail Cactus, making it a friendlier cacti for homes with small children and pets.

Bishop's Cap

Bishop’s Cap Appearance

The young Bishop’s Cap cactus starts out as a round plant. As the cactus ages, the plant develops four to eight ribs giving it a bulbous, star shape. Blooming indoors occurs more often than other cacti. The flowers produced are yellow and resemble daisies. White, hairy scales will develop on the Bishop’s Hat as it matures. This is natural and is not an indication of disease or distress.

Bishop’s Cap Light Requirements

Avoid placing young Bishop’s Hats in very bright sunlight as it will lead to scorching of the plant’s surface. Give the young cactus plenty of filtered light or light shade. Mature plants tolerate bright light but from a distance. The Bishop’s Cap cactus is not tolerant of full sun.

Water Needs

Water your Bishop’s Cap once every two weeks in the spring and summer for optimal growth. Allow the soil to dry between waterings to avoid root rot. Decrease waterings beginning in the fall when temperatures cool. Withhold water in the winter months when the plant will naturally go dormant. Slowly introduce water again in the spring and then commence with giving water once every two weeks as the plant begins its growth phase

Temperature and Humidity

Temperature and Humidity

Keep temperatures for the Bishop’s Cap cactus around 70 degrees Fahrenheit ( 21 degrees Celsius) during the spring and summer. Begin to introduce cooler temperatures in the fall, then keep the Bishop’s Hat at around 50 degrees Fahrenheit ( 10 degrees Celsius) during winter dormancy. Humidity of around 50 percent is sufficient for this cactus.

Soil and Fertilizer

The Bishop’s Cap requires a well-draining soil mix. Use a cactus or succulent soil or create your own mixture of 25% coarse sand, 25% pumice, and 50% potting soil. Place a thin layer of sand over the surface of the soil to help protect the neck of the cactus. Grow your cactus in an unglazed, clay pot to allow excess moisture to wick away from the soil and decrease the chance of bacteria or fungi formation. Use a low-nitrogen fertilizer, in the spring and summer only, to encourage growth and blooming. Feed once per month at most.

Bishop’s Cap Propagation

The Bishop’s Cap cactus will propagate by seeds collected from its blooms. Lightly press the seeds into a cactus soil mixture. Keep the temperature around 78 degrees Fahrenheit ( 25.5 degrees Celsius) and the soil lightly moist. After the seeds germinate, and some growth occurs, transfer each new cacti to its own terra cotta pot filled with the same soil mixture. Give the young plants filtered light, regular waterings, and temperatures around 70 degrees Fahrenheit (21 degrees Celsius).

Bishop’s Cap Propagation
Gardening Know How

Disease and Pests

The Bishop’s Hat is mostly resistant to infestations but is susceptible in the winter if the plant is not kept cool and dormant. Mealybugs and scale are the most common pests. Remove adult insects with a cotton swab soaked in rubbing alcohol. For large infestations, treat the entire plant with either neem oil or an insecticidal soap

Brown patches on mature plants occur naturally and are of no concern. If brown patches appear on young plants it is a sign of stress due to overwatering. Reduce the amount of water given and ensure the soil dries out between waterings.

The Bishop’s Cap cactus is a unique cacti with an adorable star-like shape. It can be handled easier than most cacti because of its lack of thorns and is considered low maintenance. Its impressive size makes it a great addition to airy spaces or as a focal point in a grouping of plants. 

Bishop’s Cap FAQ

When Should I Repot My Bishop’s Cap Cactus?

Repot this cactus in the early spring before significant growth begins. Repot only once the cactus has outgrown its current pot. 

Can I Grow the Bishop’s Cap Cactus outdoors?

Yes, the Bishop’s Hat will grow outdoors in USDA zones 10 and 11. Avoid placing the cactus in full sun. Instead opt for dappled sun or light shade.

Is it Normal for My Bishop’s Cap to Have White Scales?

Yes, these white scales appear on mature plants and are a protective coating. Do not remove the scales and take care not to damage them during handling.

Is the Bishop’s Cap Cactus Toxic?

No, the plant is not considered toxic to pets or humans.

How Large Does the Bishop’s Cap Cactus Get?

Mature plants can reach a height and width of between 23 to 39 inches ( 58 to 99 cm).