Curcuma alismatifolia, is a stately and elegant summer-blooming flower. This heat-loving, long-blooming, tropical plant produces gorgeous spires of flower bracts in colors of pink, purple, or white in abundance all summer long. It is a repeat bloomer. Curcuma is a rhizomatous tropical perennial in the ginger family that grows up to 2’ tall. Commonly called Siam tulip, it is native to Thailand (formerly known as Siam). It acquired the tulip part of its common name because its flower heads, stems and leaves resemble those of tulips. Each flower head reaches up to 3” and consists of showy, petal-like, bracts that surround the tiny, lavender-white, true flowers. You can only see the tiny true flowers if they curl around the edges of the bracts. Each flower head appears atop a rigid, reed-like stem that grows up to 2’ tall from a clump of narrow, lance-shaped, dark green leaves. Curcuma is deer and rabbit resistant and easy to grow. It makes a lovely statement when grown by itself, but also makes an outstanding addition to garden beds and borders, as well as container gardens. Curcuma looks great planted with blue salvia, caladium and other flowers. It is also an excellent choice to use with tropical plants, such as hibiscus and elephant ears in containers or beds. It also makes a beautiful tabletop centerpiece on a deck or patio. Curcuma can be grown indoors, but it will go dormant in the winter months. The plant can grow back after dormancy if the rhizomes are correctly cared for during that stage. Even though it is a member of the ginger family, curcuma is not intended for animal or human consumption.
Curcuma is a relatively easy plant to grow. It will grow in sunny or shady areas. If placing it in a sunny area, afternoon shade is preferred. In full sun, especially in hot climates, it’s helpful to keep the soil moist. If your soil tends to dry out often, it’s best to grow this plant in partial shade. It holds up better to dryer conditions if it is in a shady spot. Curcuma prefers moist, well-drained soil that has a lot of organic matter, such as compost, in it. If your soil has a high sand or clay content, add organic matter before planting for optimal performance from your plant. Water curcuma regularly when there has not been enough rain. It thrives with about an inch of moisture each week while it’s actively growing. Fertilize curcuma during spring and summer with any general-purpose fertilizer. Follow the directions on the packaging for application rates. Curcuma plants will grow and bloom well without being deadheaded. However, you can remove the faded flowers if you like to keep the plant looking fresh. Trim curcuma in autumn, when the foliage dies back to keep the garden tidy. Either treat it as an annual plant at this time or consider saving the rhizomes to keep them from freezing through winter.
Curcuma is often treated as an annual plant in zones with cold winters. Although, you can store the curcuma rhizomes through winter and plant them again in spring. Dig rhizomes from flowerbeds in fall after the first frost or when the foliage begins to yellow. Gently remove top growth and loose soil. Let them dry in a warm spot for a day or so. Store them in a cool, dry location in peat moss or vermiculite in an unsealed, breathable container. Sprinkle just a small amount of water in the medium periodically to keep them from drying out completely. Plant the rhizomes outdoors (4 inches deep) after the chance of frost has passed. For curcuma in containers, you can stop watering the container once the foliage starts to turn yellow. Remove other plants that may be growing with the curcuma. Let the potting mix dry and trim back the foliage. Store the container in a cool place for winter. Provide just a small amount of water periodically to keep the soil from drying out completely. Bring your curcuma back outdoors to a shaded or partly shaded spot in spring after all danger of frost has passed. If your curcuma has been growing as a houseplant, it will start to yellow and die back when the days get shorter. You can follow the same instructions above for containers to give the plant a rest over winter.
Hoffmann Hillermann Nursery & Florist 