Costus speciosa, also named Costus speciosus, Crape ginger, Crepe ginger and Malay ginger, can grow to 6 feet tall in frost-free areas. Costus speciosus is native to the Malay Peninsula of Southeast Asia, but it has naturalized in some tropical areas, including Hawaii. It's related to the gingers and was originally part of the Zingiberaceae family, but now the Costus species have been reclassified into their own family, Costaceae. As with most gingers, this plant is easy to grow with virtually no pest problems. Costus speciosa is best used for dramatic effect in a tropical landscape.
Crepe ginger is a tall and dramatic landscape plant with large dark green leaves, up to 20 cm long or more, about 4-6 cm wide, arranged on the stalk in a spiral.
The crepe ginger is beautiful for its bold tropical foliage, and the flowers are just an added bonus. It produces red bracts with white flowers. The flowers appear in late Summer or early Fall, and are quite unusual looking. They form on red 4 inches cone-shaped bracts, with several 2 inches pure white crinkled flowers protruding from each cone. The flowers look like crepe paper, thus the common name of crepe ginger. After the flowers fade away, the attractive red cone-shaped bracts remain.
Crepe ginger grows from thick fleshy roots called rhizomes. A single rhizome will produce new shoots and increase to a 3 feet wide clump in the second year under ideal growing conditions. It's important that the rhizome be kept dry during Winter, but in Spring, when growth starts, it should be well fertilized and watered.
Hardiness zones 7-11, (5ºC/40ºF, -15ºC/5ºF) in Winter. This is the most cold-hardy of the spiral Gingers. For best results, this plant should get from 3 to 5 hours of direct sunlight daily, and be grown in fertile, organic, moist but well-drained soil. Requires consistently moist soil; do not let dry out between waterings. Monthly applications of a balanced fertilizer during the Summer growing season will benefit this plant.
Soak seeds overnight in warm water. Plant 1/2" deep in mixture of rich soil. Keep warm, moist and in bright light. Germination can be slow.