This Astrophytum myriostigma, commonly referred to as Bishop’s Cap, is a star-shaped, spineless cactus that usually has between 4 to 6 ribs. Amy purchased this particular plant at a Phoenix-area nursery about 12 years ago. It was in a 4-inch pot and the lone yellow flower on top caught her eye – it really was just like the cap (they are called mitres) that bishops in the Episcopal church wear. It made her smile.
With just the right amount of neglect – numerous family dogs have knocked the poor potted cactus over dozens of times – and filtered sun, this Bishop’s Cap has thrived. It takes almost no water from October through March and just a bit through the summer.
Its dark green skin is covered in numerous, small, silvery glochida. As you can see, this plant now bears lots of sweet, yellow, summer blooming flowers that open in the morning and close at night. Commonly available garden literature says the plant can grow to heights of 2 to 3 feet. This one is probably about 12 inches tall.
Bishop’s Cap needs a well-drained soil that’s porous, but each time this one gets knocked over, it gets re-potted in whatever soil is handy. It likes filtered shade and can take cold temperatures, down to about 20 degrees fahrenheit. This plant is native from southern Texas to the north central Mexican plateau and will regrow from the root if the top is cut off (let’s hope the dogs don’t figure that out).