Echinocactus is a genus of slow-growing, barrel-shaped or hemispherical cacti in the family Cactaceae, comprising about six species. It grows well in full sun and well-drained soil. Yellow-flowered species are easier to grow. Propagation is by seed in spring.
Echinocactus grusonii (Golden Barrel Cactus, Mother-in-Law's Seat (Cushion), or Golden Ball) is a well-known and popular species of cactus native to Central Mexico. It is widely cultivated in warmer climates around the world. Echinocactus grusonii is a slow-growing and spherical cactus. Its spined green stem has 30-35 ribs, with the woolly crown bears a ring of yellow-colored flowers in summer. The sharp spines are long, straight or slightly curved, and in various shades of yellow. Flowering only occurs on stems that are over 38 cm wide. It can grow up to 2m high and across.
Echinocactus platyacanthus (Giant Barrel Cactus, Large Barrel Cactus) is a slow-growing, hemispherical cactus. I can grow up to 3 m high and 2 m wide. The gray-blue stem has a woolly crown and up to 50 ribs. In summer, funnel-shaped yellow flowers are borne on plants over 40 cm wide.
Echinocactus polycephalus (Cotton Top Cactus, Harem Cactus, Woolly-headed Barrel Cactus) is a cactus native to Mojave Desert and northern Sonoran Desert. The stem may occur solitary or in clusters of up to 30. Each catus are up to 60 cm tall. The long spines are yellow to red color, and its fruits are densely woolly.
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