This is a genus of ground-dwelling, stemless bromeliads that make their homes amid tree roots and in rock fissures in their native Brazil. They are commonly called earth stars. The dramatic foliage is rosette-forming, strongly marked, and highly colored, often with prickly edges. As airplants, they take little through their roots in the way of nutrients, using them chiefly for anchorage.
The small, white flowers are usually hidden in the leaves, hence the Latin name, meaning “hidden flower.” These plants are ideal for growing in a bottle garden or terrarium. The leaves of C. bivittatus form a dense, spreading rosette and can reach 8 in. (20 cm) in length. They are sharply pointed and dark green with two broad, white or pink bands running along their length. Diameter to 1 ft. (30 cm). C. bromelioides, known as rainbow star, grows upright, rather than flat, and spreads by stolons with plantlets at the ends.
Its leaves are 4—8 in. (10—20 cm) long and olive-green or variegated. The variety C.b. tricolor has leaves that are striped lengthwise with light green and cream, flushed rose-pink in bright light. This is not one of the easiest plants to grow since it is inclined to rot at the base. Height to 18 in. (45 cm). C. fosterianus is one of the largest species of Cryptanthus, with a flat rosette of thick, fleshy leaves that can reach up to 1 ft. (30 cm) in length, in shades of copper-green or purple-brown, banded with gray. Diameter 20 in. (50 cm).
Size: See individual species.
Light: Direct sunlight.
Moisture: Keep barely moist at all times.
Feeding: Give only an occasional spray with half-strength foliar fertilizer to improve leaf coloration.
Propagation: Use a sharp knife to detach offsets in spring. They root in about 12 weeks. C. bromelioides produces plantlets that can be treated as offsets.
Special needs: After flowering, cut away the parent plant to allow the new offsets to develop.