These tropical plants are tender perennials from India, China and the East Indies and they have thick fragrant rootstocks, resembling the scent of ginger, from which the new shoots sprout in the spring. They can grow up to 10 feet high with a 3-foot spread. Their leaves are lance-shaped with fringed borders and they are produced on reedy stems. The tubular flowers are produced in pendulous clusters. The colors vary among the different kinds. Some are white with yellow lips and have a throat stained with pink, some are white tinted with purple, and some are red and yellow.
When these plants are grown in a greenhouse, a minimum temperature of 55 degrees in the winter is required. March is the best time for repotting. The best compost to use consists of equal parts of loam, leaf mold and well-decayed manure. The rhizome should be set about an inch below the surface. They may be divided every year and kept in 6-inch pots, or they may be left alone to grow into big plants that will fill large tubs. They love moisture, so they don't need a huge amount of drainage. The soil should be constantly moist throughout the summer and the atmosphere very humid by spraying the leaves, floor and benches of the greenhouse. They should be given fertilizer every two weeks when they are growing actively. Shade from direct sunlight should be provided. When they are finished flowering, they should be watered less, just enough to keep the soil from drying out completely. In the far South, these plants may be planted outside in rich soil in partial shade.
The best way to increase your plants is to divide the rhizomes into pieces in spring or early summer. Pot these pieces separately in small pots and later into larger ones. They may also be raised from seeds.