Astrophytum - Bishop's Cap, Bishop's Miter, Goat's Horn Cactus, Monk's Hood, Sea-Urchin Cactus, Silver Dollar Cactus, Star Cactus

(Astro'phytum)

DESCRIPTION: This popular group of cacti consists of only four wild species and maybe a dozen hybrids. These natives to Mexico are suitable for growing in greenhouses, windowsills and outdoors where climates permit. Most of these cacti form short, spherical plants that may or may not have spines. They are usually flecked with small, white scales. In spring to late summer, numerous, large, daisy-like, yellow flowers grow at the plant's crown. Each long-lasting flower opens completely in bright light. They are followed by pulpy, green seedpods, which break open to expose large seeds. A. asterias (Sea Urchin Cactus; Silver Dollar Cactus) is a spine-less cactus that forms a perfectly round plant. This species grows up to 2 inches high with a spread of 5 inches. The body of this cactus has flat, grayish- to whitish-green ribs that are flecked with small, white spots. Some plants are speckled heavily; while others are not. After about five years, pretty flowers, 2 inches wide, are produced throughout the summer. They are yellow with dark red throats. In the winter, when dry and dormant, this plant shrinks to a flat disc. A. capricorne (Goat's Horn Cactus) is an interesting plant that can grow up to 4 feet high with a spread of 4 inches. The dark colored body is covered with very long, gray or brown, twisting spines. The spines are easily broken off if handled. Its bright yellow flowers have a red throat. A. myriostigma (Bishop's Cap; Bishop's Miter; Monk's Hood) is another interesting variety that grows up to 6 inches high with a spread of 8 inches. The Bishop's Cap has a purple, green, or blue body with 4 to 8, spineless ribs. This plant eventually becomes somewhat columnar with age. The amount of speckling varies from plant to plant. Large plants produce large, yellow flowers up to 21/2 inches across throughout the summer. A. asterias var. Super Kabuto is a hybrid with very large, white flecks. Seedlings of this variety may be produced with almost no speckles to speckles that cover the entire plant. This hybrid tends to be slower growing.

POTTING: Grow these cacti in well-drained potting soil. An addition of ground limestone will benefit the plant's roots and vigor. Take care when watering as these plants may rot.

PROPAGATION: Seeds and cuttings may be used.

VARIETIES: A. asterias & var. Super Kabuto; A. capricorne; A. myriostigma & var. Nudum, monstrose Lotusland; A. ornatum (Star Cactus); A. coahuilense.

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