Curcuma

Do you have a warm-temperature garden? Then, the Curcuma plants will thrive in your landscape. This elegant summer blooming flower looks great in container gardens.

The Curcuma genus includes plants that will add a tropical feel to your garden. The plant’s lengthy stems with slightly hidden flowers look like pinecones giving it the name hidden cone gingers.

I. Appearance and Characteristics 

Curcuma is a genus of plants in the family Zingiberaceae that contains such species as turmeric and Siam tulip. They are native to Southeast Asia, southern China, the Indian Subcontinent, New Guinea and northern Australia. Some species are reportedly naturalized in other warm parts of the world such as tropical Africa, Central America, Florida, and various islands of the Pacific, Indian and Atlantic Oceans. Generally, most curcuma grows well in loose and sandy soil in shaded areas.

Curcuma is a perennial, herbaceous plant that can reach a height of 1 meter. It emits numerous, edible rhizomes whose interiors are yellow or orange. These rhizomes are reduced to a powder, which is the spice called curcuma. Its lanceolate leaves are oblong or elliptical and are of a uniform green, and about 50cm long and 7 to 25 cm wide.

II. How to Grow and Care

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.

Sunlight

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.

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.

Watering

The Curcuma loves constant moist soil and can withstand heavy rainfalls if the ground is free-draining. Never let the potting mix dry, or else, it will lose its green foliage.

You can water them well once a week from spring to summer. If there’s scorching weather, check the soil’s moisture level from time to time. If you find the top few inches dry, you need not water but if it dries out more, then quench its thirst with watering.

As an outdoor plant, you can add mulch to help retain moisture and layered about two inches deep. In addition, you can reduce your watering schedule in fall and winter as it becomes a dormant plant.

On the other hand, if you grow Curcuma as an indoor plant, make sure that it has well-drained soil. Take note that pots can dry fast, so it’s best to keep an eye on the moisture as it will need more watering in the growing season.

Soil

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.

Fertilizing

Your perennial will bloom when you feed them a soluble fertilizer like 20-20-20. You can apply a tablespoon of feed per square foot where your plants grow.

Provide your Curcuma with fertilizing in spring when new growth appears. Adding some manure or compost also helps to provide the nutrients it needs.

Potting and Pruning

Before the winter arrives or in early spring after the last frost passes, you can sow your Curcuma in the ground. While they grow in spring, the best benefits you reap will be in summer, so do not rush it. After the frost passes and the weather remains cold, wait before planting them.

Whether you decide to develop them in your garden or a pot, the crucial thing is drainage with some gravel layered at the base. You can place the rhizomes about three inches deep, and for planting in the landscape, leave about a foot between each Curcuma.

As summer arrives, your plants greet you with bunched flowers that are mildly fragrant for about four weeks. You will see that the foliage is dense, and the green foliage appears with lance-shaped leaves.

After flowering, grab your sterilized pruners and cut the flower spike down to four inches above the ground. You need not trim your Curcuma during the growing season but can remove the brown leaves.

Propagation

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.

Pests and 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.

Winter Protection

As the vegetation is perennial, it does go dormant in cold weather. To protect Curcuma, you can cut them down as it will keep them protected growing outside.

Still, if you grow their containers, you can bring them inside if the temperature drops below freezing point.

III. 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.

IV. Common Problems with Curcuma

Curcuma primarily experiences fungi and disease when the water balance is not maintained. Here are some common issues:

Curling Leaves

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.

Not Flowering

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.

V. Uses and Benefits 

The name is derived from the Sanskrit kuṅkuma, referring to turmeric. Turmeric is used to flavour or colour curry powders, mustards, butters, and cheeses; it may also be used as a substitute for saffron or other yellowish pigments.

Curcuma are easy to grow and bring that tropical look to cooler region gardens. They are an ideal plant for wooded gardens, tropical style gardens or, smaller varieties, planted in pots. Their large showy flowers will stand out in the garden and can also be used as a cut flower.  If you have chosen an edible plant then the dried rhizome of the Curcuma plant is ground up to use as the culinary Turmeric, and the flowers and young leaves of this plant can be used as a vegetable. In Indonesia, the young shoots and rhizome tips are eaten raw while the leaves are used to wrap around fish to add flavor during cooking.