There are more than 60 species of curcumas, most of which are native to India, Sri Lanka and Thailand. Curcumas are commonly called hdden gingers or surprise gingers because the flowers often grow at the base of the plants. They are also called queen lilies or turmeric gingers.
Curcumas range in height from 1 to 8 feet. The foliage may be solid green or variegated with white or red coloration. Small flowers appear in waxy bracts that resemble pine cones or tulips in the summer. The bracts are shades of lavender, pink, green and white. The flowers last a long time, either on the plants or as cut flowers.
Curcumas have short fleshy rhizomes and tuberous roots. They should be planted 4 inches deep in well-drained soil. Curcumas will grow in sun to partial shade, but the color of the bracts will be more intense in full sun. They should be fertilized in the spring following the manufacturer's recommended rate of application.
Soil that is too wet in the winter may cause root rot. Curcumas grow in Zones 8 to 11 and go dormant in the winter, even in warmer climates.
Curcumas With Cone-Shaped Bracts
Most species of Curcumas have cone-shaped bracts, such as C. petiolata, which has white bracts. C. elata (Giant Plume Ginger) is the earliest to bloom and has soft pink bracts. C. cordata also has soft pink bracts, while C. australiasica (Aussie Plume Ginger) has bright pink. The bracts of C. roscoeana are bright orange.
Curcumas With Tulip-Shaped Bracts
Some species of curcumas have tulip-shaped bracts, like C. alismatifolia (Siam Tulip) with white, pink or lavender bracts. 'Precious Patuma' has pink bracts with green tips. The bracts of 'Chiang Mai Snow' are pure white.
The underground stems of turmeric ginger (Curcuma longa) are dried and ground to produce the spice called turmeric. It has a bitter taste and a golden color. Turmeric is used to flavor curry powder, mustard and cheese. It is also used as a dye.