Echinocactus

This group consists of six cacti native to Mexico and the southwestern U.S. These globular- to barrel-shaped plants (Hedgehog Cactus) vary in size from small plants only 41/2 inches wide to giants 3 feet wide and 61/2 feet high, weighing more than 2,200 pounds. These plants produce a ring of open-faced flowers on the plant's crown ranging in color from golden yellow to purplish-red. These cacti are suitable for growing in containers in a greenhouse or home and as landscape plants. E. grusonii (Golden Barrel; Mother-in-law's Chair) is an attractive species that grows up to 4 feet high. It is barrel-shaped and ribbed with sharp, golden yellow spines, which become dense and have a richer color in full sun. Plants grown in containers often take 30 to 40 years to reach a flowering size of about 15 inches in diameter. Their yellow flowers, which are produced from a crown of yellow wool, need full sun in order to stay open for a long time. E. horizonthalonius (Eagle Claws; Mule Crippler) is a pretty species with straight or recurved, flattened spines and a silvery-gray exterior. In the spring and summer, 3-inch long, pink flowers are borne.

Pot Cultivation

These succulents need a minimum temperature of 50� F and full sun. The best compost to use for these plants consists of four parts sandy loam, and one part of equal quantities of coarse sand and crushed brick. Repotting should be done in April, but they really only have to be moved into larger pots if the growth in unsatisfactory. They do well when the roots are cramped in small pots. The pots need to have adequate drainage with the compost packed firmly with a potting stick. After potting, no water should be given until the soil is fairly dry. Well-rooted plants can be watered freely from April to August after which the water supply is gradually decreased until just enough is given throughout the winter to keep the stems from shriveling.

Propagation

Seeds can be sown in pots of sandy soil in the summer. They should be covered thinly with sifted soil and a pane of glass until they start to grow. Once they sprout, the glass is removed and the seedlings are later planted one inch apart in pans of fine soil. When they are large enough, they are potted in small pots. Rarely do side shoots form, but if they do, they can be plucked off and inserted as cuttings.

E. grandis;

VARIETIES

• E. grandis;
• E. grusonii;
• E. horizonthalonius;
• E. platyacanthus (also known as E. palmeri);
• E. ingens (Mexican Giant Barrel);
• E. polycephalus.