Crepe ginger's spiral stems can be seen in this clump of crepe ginger in Hawaii.
Crepe ginger is a tall and dramatic landscape plant with large dark green leaves arranged on the stalk in a spiral. This Costus can grow to 10 ft (3.1 m) tall in frost-free areas, but typically grows to about 6 ft (1.8 m) tall in cooler regions where it is root hardy but dies back in winter.
The flowers appear in late summer or early fall, and are quite unusual looking. They form on red 4 in (10.2 cm) cone-shaped bracts, with several 2 in (5 cm) 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.
As beautiful as the species is, there are a number of cultivars of Costus speciosus that are sought after as garden ornamentals. Most are not as hardy as the species and do not grow as tall. The cultivar 'Pink Shadow' is similar to the species but the white flowers are blushed with pink. The cultivar 'Variegatus' has green and white variegated leaves, flowers similar to the species, grows to 5-7 ft (1.5-2.1 m), but is only hardy to zone 9. The cultivar 'Foster Variegated' has reddish stems and broad creamy white striped leaves which are soft and furry to the touch. It only grows to 5 ft (1.5 m) tall and is less likely to flower than the species. The cultivar 'Nova' is a shorter plant, to about 3 ft (0.9 m), and has light green foliage and flowers similar to the species. Another short tetraploid is offered by Stokes Tropicals, and the description is similar to 'Nova'.
NOTE: some taxonomists still classify Costus and related genera in Zingiberaceae, the ginger family.
Location Costus speciosus is native to the Malay Peninsula of Southeast Asia, but it has naturalized in some tropical areas, including Hawaii. It is listed as a potential invasive plant in the Federated States of Micronesia, Guam, Republic of Palau, and in French Polynesia.
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. Monthly applications of a balanced fertilizer during the summer growing season will benefit this plant. Generally crepe ginger is pest free. Crepe ginger grows from thick fleshy roots called "rhizomes", similar in appearance to the "ginger root" found in grocery stores. They may be purchased as potted plants or as bare rhizomes, and they are easy to grow either way. Plant the rhizome about 1 in (2.5 cm) below the surface in a sandy loam or clay soil that has been improved with leaf mold or well composted manure. A single rhizome will produce new shoots and increase to a 3 ft wide clump in the second year under ideal growing conditions.
Light: Prefers part sun but will grow in full sun if it gets plenty of moisture.
Moisture: Requires regular moisture but not standing water. Hardiness: USDA Zones 7 - 12. This is the most cold-hardy of the spiral gingers, and has been tested and proven root hardy down to 0°F (-17.8°C). Propagation: Pieces of the rhizome, division of the clumps, or stem cuttings. Costaceae are the only gingers that can be propagated by stem cuttings.
Crepe ginger is a large tropical plant with showy flowers and handsome foliage.
Crepe ginger is best used for dramatic effect in a tropical landscape, but also combines well with other tall perennials as a backdrop.
The crepe ginger is beautiful for its bold tropical foliage, and the flowers are just an added bonus. As with most gingers, this plant is easy to grow with virtually no pest problems.
Many gingers have culinary or medicinal uses. This species is not commonly used in western cultures, but the rhizome has been used in India and Southeast Asia to treat boils, constipation, diarrhea, dizziness, headache, vertigo, ear, eye, and nose pain, and to stop vomiting.
The ancient Indian literary classic, the Kama Sutra, gives a use for this plant to attract a person of the opposite sex:
"An ointment made of the tabernamontana coronaria, the costus speciosus or arabicus, and the flacourtia cataphracta, can be used as an unguent of adornment. If a fine powder is made of the above plants, and applied to the wick of a lamp, which is made to burn with the oil of blue vitrol, the black pigment or lamp black produced therefrom, when applied to the eyelashes, has the effect of making a person look lovely."
In tropical areas this plant may be invasive.