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 leis and flower arrangements, but an added advantage is that many are fragrant. Moist humid tropical climates have the potential for rot and decay. This means bad smells, so by adding colorful and fragrant plants to the landscape, we can actually help to mask unwanted odors. Gingers are among the easiest of 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 due to 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 over 400 species in the family, the majority of which are native to tropical regions of the Southeast Asia. Most genera are well adapted to Hawaii’s varied climate. Many grow in the tropical zone, but some will thrive at 5,000 or more feet in 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 over-powering 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 the soil keep 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.
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 wilds, this is still one of the best for garden fragrance and lei flowers.
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.”
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 the wet, higher elevations. Since the National Park Service 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, park officials would probably prefer it if gardeners adjacent to the Hawaii Volcanoes National Park avoided planting kahili ginger altogether.
This information is supplied by the UH College of Tropical Agriculture and Human Resources.