Curcuma is a genus of plants native to the tropical regions of Asia. You’ll know Curcuma, which belongs to the ginger family Zingiberaceae, by their eye-catching, angular blooms on tall spiked stems. The Southern Living Garden Book describes them as «a group of highly ornamental gingers, » including turmeric and Siam tulip plants.
Curcuma bloom in summer. During the flowering season, tiny, bright blossoms appear on the plant’s lengthy stems, adorned with long, green, lance-shaped leaves. These plants can be reliably grown in the Coastal and Tropical South, often found along the Florida coast.
|Common Name||Turmeric, common turmeric, turmeric root|
|Botanical Name||Curcuma longa|
|Plant Type||Perennial, Herbaceous, Annual, Bulb, Rhizome|
|Mature Size||3 to 4 ft. tall, 3 to 4 ft. wide|
|Sun Exposure||Full, Partial|
|Soil Type||Moist, Well-Drained, Organic|
|Soil pH||Slightly Acidic to neutral (6.0 – 8.0)|
|Flower Color||Gold, Yellow|
|Hardiness Zones||Zones 8-11 (USDA)|
Curcuma is relatively easy to grow indoors and outdoors as part of the ginger family. Depending on growing conditions, grow Curcuma as an annual or perennial summer plant. This plant does not spread quickly, so it is ideal for container gardens.
Curcuma thrives in daily sunlight, tolerating high moisture levels and at least six hours of full sun. If you live in a region with scorching temperatures, allow Curcuma to rest in the afternoon sun.
The most critical factor in Curcuma’s soil is that it is well-draining. Adding organic matter before planting will help achieve a loamy soil consistency. Well-drained soil also helps oxygenate the plant, allowing plenty of air to flow and absorb nutrients.
Keep the soil wet to ensure Curcuma never dries out. Typically, this plant needs watering once weekly in the spring or summer. You can use less water during dormancy in the winter.
Temperature and Humidity
The best growing conditions for Curcuma are humid environments with ample rainfall—moderate to warm temperatures. Curcuma goes dormant in colder weather and will not survive past the first frost.
Use a 20-20-20 soluble fertilizer every month. Curcuma requires a lot of nutrients, so fertilizing in the spring and summer will help encourage growth.
Types of Curcuma
- C. petiolata: This is the best-known variety of the Curcuma, also known as a hidden lily or queen lily. These plants grow two to three feet high with yellow or purple bracts, and elongated leaves.
- «Emperor»: A popular selection that produces gray-green leaves with touches of white alongside white flower spikes tinged with purple. These are, in a word, stunning.
- C. Alismatifolia: Siam tulip has small leaves and pink or white bract clusters.
- C. Elata: Known as a giant plume, it grows to seven feet under optimal conditions and produces pink and yellow flowers.
- C. Gracillima: Colorful and eye-catching, «Candy Cane» is red-and-white striped.
- C. Longa: «Bright White,» which is so white it practically glows in the sun.
- C. Roscoeana: This variety has orange and yellow flowers.
- C. Zedoaria: This variety has red-striped leaves, red bracts, and yellow blooms.
Prune Curcuma in the fall after the foliage dies. Deadheading flowers is optional as it might improve appearances. Curcuma grows and blossoms even if you choose not to deadhead flowers. Use pruning shears to cut the flowers close to the ground and remove brown leaves when the plant does dormant.
Propagating Curcuma is possible through dividing rhizomes. Dig up roots in the fall at the end of the bloom season. Here’s how:
- At the end of the season, dig up the Curcuma roots—you can tell the blooming season is over when the leaves start to turn yellow.
- Choose healthy roots and avoid moldy, shriveled, or rotten ones.
- Clean dirt from the rhizome and keep it in a cool, dark, and dry location until you are ready to plant it—usually in the spring or late winter.
- Divide the rhizomes into sections, and leave a few «eyes» or buds in each section to help secure the roots when planted.
- Plant the rhizomes in a container or garden in two to four inches of organic soil. Leave the «eyes» or buds facing upwards. New growth should sprout in seven to ten months.
Common Pests & Plant Diseases
Root rot is a common disease in the soil, a fungus caused by overwatering and often attached rhizome plants.
Bacterial wilt occurs when soil temperatures rise, causing rapid yellowing and spotting on leaves. It can hollow the plant’s stem due to decay if left untreated. Leaf blotch and leaf spots can also happen when temperatures are high or leaves are overwatered.
If the soil is overly dry, spider mites may attack, but a mild insecticidal soap treats these pests. Young leaves are also susceptible to slugs and snails.
How to Get Curcuma to Bloom
Curcuma bloom in summer through fall and produce vibrant, trumpet-shaped flowers in various hues, including pink, purple, and white. As a member of the ginger family, the leaves have a bitter fragrance. The showy flowers sit on top of bright, lance-shaped leaves.
Keeping Curcuma in moist, well-draining soil helps increase its bloom time, producing around five new flowers lasting up to three weeks.
To plant Curcuma in your garden, The Southern Living Garden Book advises to «plant in spring, setting rhizomes one inch deep in moist, well-drained, humus-rich soil. Plants die down in winter and need very little water during dormancy.» They’re great picks for bedding plants and can also make a statement thanks to their gorgeous foliage and vibrant blooms.
Common Problems With Curcuma
Curcuma primarily experiences fungi and disease when the water balance is not maintained. Here are some common issues:
Bacterial wilt is the most likely culprit of curling leaves. Avoid excess water runoff from other areas of your garden—planting Curcuma on a hill helps achieve this. Plant Curcuma in the same soil as previously harvested mint or lemongrass, which contains pathogens that can suppress bacterial wilt from forming.
Leaves Turning Brown
If Curcuma leaves turn brown, this doesn’t mean your plant is dead, but it is a sign that it needs more water. Browning leaves signify plant dormancy, which occurs at the end of the blooming season. Early leaf browning happens if your soil is too dry, so ensure to water the roots at least once a week adequately.
If the Curcuma plant is not flowering, this is a sign of inadequate light, malnutrition, or possible winter damage. Position Curcuma in an area that receives at least six hours of sunlight daily, but be sure not to scorch the plant. Maintain healthy and nutrient-rich soil so it is a loamy consistency. Depending on your region’s climate, a dormant plant may have experienced too harsh cold-weather conditions, which can prevent growth.
Have you ever encountered any Curcuma species in your area? Do you have any growing in your garden?