Bird Rock Tropicals
Cryptanthus

The genus Cryptanthus consists of about 50 terrestrial species commonly called earth stars because of their shape.  The plants have low-spreading rosettes of six to 20 leaves.  The succulent usually tooth-edged leaves may be spoon-shaped, lance-shaped, or triangular, from three to twelve inches (8-30 cm) in length.  Most are in the three- to six-inch (8-15 cm) range.  They are usually strongly banded or frosted with gray, white or bronze, and many cultivars have a pink to red background color.  The various hybrids show a rainbow of colors, and the most popular cultivars have very elaborate banding with sharp zigzag patterns.  The white (sometimes light green or pink) flowers appear in the center and from between the leaves, a few at a time.  They are so popular that there is a separate Cryptanthus Society affiliated with The Bromeliad Society.  

LIGHT:  About 2500 to 3000 foot candles of light is appropriate for most, which translates to 55 % to 75% shade cloth in sunny climates.  With too little light, foliage color and strong markings fail to develop.  At the other extreme, too much light bleaches foliage colors.  They do well on patios where the area is lit by morning or afternoon sun but not directly on the plants.  The colors change with the seasons and amount of light.

TEMPERATURE:  Cryptanthus tolerate a temperature range from 40° F to over 100°F (4° to 38° C).  Optimum growth occurs between 60 to 85 ° F (15° to 30° C).

AIR:  Cryptanthus prefer at least moderate humidity and perform well when grown on or near the ground among ferns or begonias, or close to ponds.

WATERING:   Keep the medium moist at all times.  Cryptanthus suffer if they dry out for extended periods. 

POTTING AND MOUNTING:  Cryptanthus are true terrestrials; they do not absorb water or nutrients through their leaves.  They develop strong root systems and are not suitable for mounting.  They prefer a more water-retentive medium than most other bromeliads, but it still must drain rapidly.  Do not underpot; at least a five  or six inch pot is recommended.  Use a loose, porous medium rich in peat moss or other organic material.

 FEEDING:  They respond well to generous fertilizing.  Growers recommend adding slow-release fertilizer to the potting mix and feeding with liquid fertilizer as well. 

PROPAGATION.  Offsets of some cultivars may be a little reluctant to establish.  Propagate in spring or summer.  It helps to remove the dry, rudimentary leaves at the base of the pup in order to expose the tiny root buds.

(Reprinted from Bromeliads A Cultural Manual, The Bromeliad Society, Inc.)