Daniel Gill, Bogren, Richard C. | 7/28/2008 7:54:48 PM
Get It Growing News For 08/01/08
By Dan Gill
Months of hot, humid weather make summers in Louisiana a challenge to many of the plants in our gardens. As other plants languish in the heat, a wonderful group of plants called gingers thrive and delight us with bold foliage and attractive flowers. Native to tropical or semi-tropical regions, gingers flourish in the heat, rain and humidity. Planted into the garden now, they will still have time to get established before winter.
Despite their tropical origins, many gingers are hardy around the state and make excellent, permanent additions to the landscape. Gingers produce a thick, fleshy stem that grows at or just below the soil surface from what is called a rhizome. With a good, thick mulch of leaves or pine straw, the rhizome is easily protected during the winter. If the top is killed by hard freezes, the rhizome will resprout in the spring.
Gingers belong to the Zingiberaceae family. Their large leaves – which are sometimes variegated or attractively patterned – and vigorous clumping growth habit create an effect of tropical luxuriance, which many gardeners desire. In addition, most gingers we grow feature exotically beautiful and sometimes-fragrant flowers.
The plants we call gingers actually include many genera with many different sizes, growth habits and flower shapes. Low-growing gingers, like Kaempferia pulchra – smaller species of Curcuma or Globba – make great ground covers or clumps at the front of shady borders. Medium-sized gingers 3 to 6 feet tall include species of Curcuma, Hedychium and Costus, while the shell ginger (Alpinia zerumbet) grows 8 to 10 feet tall. These larger gingers are excellent choices for accents or screens or at the back of a border.
Gardeners who are working with shady areas will find a gold mine of shade-tolerant plants among the gingers. In their natural habitats, most gingers grow under the canopies of trees in filtered light, although some grow in the open at the edge of water or in sunnier conditions. Most gingers will do best where they receive direct sun for about two to four hours a day and should not be planted in hot, sunny, dry locations. Shell ginger and some species of Curcuma and Costus will, however, grow in full sun.
Gingers thrive in moist, fertile soils rich in organic matter. When planting gingers into the landscape, choose a location with appropriate light and generously amend the soil with compost, well-rotted manure or peat moss. A 2- to 4-inch layer dug into the upper 8 inches of soil would be fine. Also, the addition of some general-purpose fertilizer will help create the nutrient-rich conditions in which gingers thrive.
Under favorable growing conditions, many gingers grow vigorously and form clumps that should be periodically dug and divided. This keeps gingers from spreading into areas where they are not wanted and prevents the clumps from getting too large. This is best done in early April, although, many gardeners successfully divide gingers through the summer if new divisions are kept well-watered. Depending on how fast the plant grows and the amount of space allotted to it, dividing and replanting is generally done every couple of years.
Gingers, such as Curcuma, Globba and Kaempferia, go completely dormant in the winter. Their foliage turns yellow and brown in the fall, and the plants should be cut back at that time. Mark where they are growing, lest you forget and accidentally dig into them while they are dormant. They will sprout again in the spring and bloom during the summer. Keep them well-mulched over the winter.
Other gingers are evergreen (if they don’t freeze back) and bloom on new shoots that grow each year, although old shoots may persist from the previous season. Plants in this group – such as butterfly ginger (Hedychium) and spiral ginger (Costus) – may be cut back to the ground in winter or early spring much as you would cannas. If plants are frozen back, all brown growth should be removed to just above ground level.
A few gingers, such as shell ginger (Alpinia zerumbet), are evergreen and bloom on the previous year’s growth. Stalks that grew the summer before should not be cut back unless killed by freezes during winter. Shell ginger rarely blooms except in the mildest areas of the state. The variegated shell ginger is shorter-growing than the standard species and reaches 4 to 6 feet tall. The green foliage with brilliant yellow streaks is truly eye-catching and has made it one of the most popular gingers today.
People have occasionally asked me about the edibility of garden gingers. I would recommend you stick with common edible ginger, Zingiber officinale, for your cooking. Rhizomes are available at the supermarket, and it has the flavor we generally are looking for when a recipe calls for ginger.
Contact: Dan Gill at (225) 578-2222 or email@example.com
Editor: Rick Bogren at (225) 578-2263 or firstname.lastname@example.org