Hawaii is blessed with a vast array of flowers, and we use them in the landscape for many reasons. Colorful flowering plants add visual beauty. They are useful for lei and flower arrangements, but an added advantage is that many are fragrant. Moist humid tropical climates have the potential for rot and decay. By adding colorful and fragrant plants to the landscape, we can mask unwanted odors. Gingers are among the easiest plants to grow for this purpose.
The ginger family is noted for its many colorful and fragrant species. Gingers are related to the banana, palm and bamboo families, in that they are monocots. This year, many of the common gingers are blooming late because of dry weather. In mauka West Hawaii, for example, kahili, white, yellow and guava jelly gingers usually start blooming as early as May. This year they started in July and are still blooming.
There are 40 genera and more than 400 species in the family, the majority of which are native to tropical regions of Southeast Asia. Most genera are well-adapted to Hawaii’s varied climates. Many grow in the tropical zone, but some will thrive at 5,000 or more feet of elevation.
Gingers are rhizomatous perennials, generally with simple unbranched stems. Flowers vary considerably, from small to very showy, and are usually borne in heads. Many of the ginger flowers are very fragrant, so fragrant in some cases that they are overpowering in a small room. Flowers and foliage of many species are excellent for use in floral arrangements. Gingers are relatively easy to cultivate, and once established, require little care. They grow well on a wide range of soil types, as long as the soil is moist at all times. River banks and land adjacent to ponds or boggy spots are choice locations, and will support the best growth. If gingers are planted on high, dry soils, frequent applications of water are necessary.
Handle gingers the same as bananas. They do best in moist soil high in organic matter. An application of fertilizer in early spring when growth begins, and two more applications at the same rate during the growing season will be sufficient. The fertilizer applications should be spaced eight weeks apart. Also, compost and well-rotted manures applied every three months will help keep the soil sufficiently rich. Planting or transplanting can be done at any season of the year. The parent clump may be divided like any rhizomatous herb, such as gloriosa lily. The fleshy underground rhizomes can be severed at any point, as long as each piece has at least one good eye to produce a new plant.
Here are some gingers to consider for your garden:
c The butterfly lily, or white ginger, with its heads of white butterfly-like flowers, is commonly found. Its extremely fragrant flowers last but a day and are constantly being replenished by a new supply. The flowering period will last for several months. Although common in the wild, this is still one of the best for garden fragrance and lei flowers.
c The shell ginger, with its 3- to 8-foot stalks of evergreen foliage, is frequently used in sunnier, drier conditions than most gingers. Its flowers, with their combination of cream, yellow and red markings, are excellent material for floral arrangements.
c The red ginger, Alpinia purpurata, is also common but very effective in the garden. It has a close relative, the Tahitian red ginger, which is rare but can be found in some local nurseries. Another relative is a pink form of red ginger called jungle queen.
c Other gingers to watch for at our local nurseries and garden shops are several forms of torch ginger, still known incorrectly as Phaeomeria magnifica in the trade. Also watch for cardamom ginger, Costus gingers, Curcuma gingers and the orange-flowered Himalayan ginger, Hedychium greenei. On the Hilo side, you will also see fields of edible ginger. The yellow ginger is common, but if you watch carefully, you will find many variations of this one.
We tend to take gingers for granted in Hawaii, where they grow so easily, but few plant materials give so much for so little work. Try several types if you have the room in your garden.
One caution to note. The kahili ginger is one that seeds and spreads in wet, higher elevations. Since the national park folks are trying to keep non-native plants out of the park, it would be helpful if the spent flower heads were removed from your garden kahili ginger plants before they set seed. Of course, officials would probably prefer it if gardeners adjacent to the park avoided planting kahili ginger altogether.