In its natural desert habitat in southwest USA and northeast Mexico, Echinocactus, also known as barrel cactus, can live for over 100 years, eventually forming a mound about 6½ ft. (2 m) across. Its shape is like a slightly flattened ball. E. grusonii, the golden barrel cactus, has a green stem of 50 ribs and buff-colored spines. The wider crown stems bear straw- colored flowers in summer.
Size: Height 5—8 in. (12—20 cm), spread 1 ft. (50 cm).
Light: Direct sunlight.
Temperature: Normal warm room temperature from spring to fall. During the winter rest period 50°F (10°C). No lower than 40°F (5°C).
Moisture: Keep soil moist from spring to fall, in winter apply just enough water to prevent it drying out.
Feeding: Use standard liquid tomato fertilizer once a month in spring and summer.
Propagation: Sow seed.
Special needs: Pot or repot in spring.