With its green, lance-shaped leaves adorned with yellow stripes and white flowers that resemble seashells, variegated ginger (Alpinia zerumbet "Variegata") is also known as shell ginger or shell flower. Although this member of the Zingiberaceae family can grow as an indoor container plant, when provided with ideal growing conditions and proper care, it grows to 6 feet tall as a landscape specimen within U.S. Department of Agriculture plant hardiness zones 8 through 10.
Location and Soil
Variegated ginger is not picky when it comes to its location in the garden -- it can grow in areas that provide at least six hours of sun and bright light throughout the day but can also thrive in partial shady areas of the garden. Well-draining, moist, rich soil is needed to grow this East Asia native. Before starting the plant, cultivate the soil and incorporate a layer of compost into it to promote soil moisture retention and provide nutrients.
Starting the Plant
Variegated ginger isn't frost tolerant, and a minimum temperature of 68 degrees Fahrenheit is required for optimal growth. Although the plant can be started from seed, starting it from pieces of the rhizome or from a nursery-bought container plant is faster. The rhizome is the fleshy root that resembles a culinary ginger root. Plant the rhizome just below the soil surface, about 1 inch deep. To grow multiple plants, space the rhizomes 1 to 2 feet apart.
Keeping the garden soil evenly moist -- not wet -- is essential, because variegated ginger prefers high humidity and doesn't tolerate drought. The edges of the leaves turn brown if the plant lacks moisture. Water regularly, especially during the initial growing season when the roots are establishing. Spread a thick layer of organic mulch over the soil around the plant to help promote soil moisture retention. After blooming, fertilize the plant with an acidic fertilizer and prune the plant as needed to control its size.
Because variegated ginger doesn't flower until its second year, it can only be enjoyed for its foliage in the cooler areas. The leaves can withstand temperatures as low as 25 degrees Fahrenheit, but if the soil freezes, the roots won't be able to overwinter. In cooler areas of USDA zone 8, a thick layer of organic mulch might help protect the roots. If unsure about the effectiveness of garden mulch, dig up the rhizome, store it at 55 degrees Fahrenheit in dry pine bark mulch, and then restart it in spring after frost danger has passed.