Black Turmeric

Black Turmeric (Curcuma caesia) is a tropical ginger grown for dramatic foliage first and an edible rhizome second. Each clump throws up broad upright leaves to about 1.2m tall and 800mm across, marked with a dark maroon stripe down the centre of every blade. Pink and purple flower spikes appear low in the clump through the warm months.

Why you'll love it

• Foliage that carries a bed on its own. The dark central stripe on a broad green leaf reads from across the garden.
• An edible crop underneath. The rhizome is a traditional ingredient in Indian cooking, deeply aromatic and used in small quantities for its bitter, pungent flavour.
• It copes with wet ground. Unusually for a feature plant it tolerates wet feet, so the low damp corner that rots other plants is fair game.
• Heat and humidity suit it. A humid subtropical or tropical summer is the weather it was built for.

Where it works best

Feature planting. One clump beside a path, a pool fence or a shaded entry does the work of a much larger plant. At 1.2m by 800mm it fills a gap without needing a bed built around it.

Mass planting. Plant 60cm apart for a lush block of foliage. At that spacing the clumps knit into a continuous mass by the second summer while each still has room to build a decent rhizome.

Pots and small gardens. A pot 400mm or wider suits it, and a container makes the winter dormancy easy: move it out of the way and stop watering.

Growing Black Turmeric in Australia

Position and climate. Partial shade, or morning sun with afternoon protection, since harsh sun scorches the leaf edges. This is a plant for tropical, subtropical and warm temperate gardens only. It is frost tender, so in cool districts grow it in a pot and keep the dormant rhizome dry.

Soil. Rich, moisture retentive and heavily composted. Unlike most ornamental gingers it tolerates ground that stays damp, though it still grows best where water moves through.

Water and feed. Water generously from the first spring shoots until the leaves yellow in autumn, and feed monthly through that period. Once it dies down, stop watering. Wet soil around a dormant rhizome is the usual cause of rot.

Pruning and dividing. Cut spent foliage to ground level once it has yellowed. Lift and divide every three or four years in early spring, which is also when you harvest.

What to expect when it arrives

Black Turmeric is sold as tube stock, so you are buying a young plant with a small developing rhizome rather than a mature clump. Give it a full warm season before you expect anything near 1.2m, and two seasons before harvesting.

Timing matters with a deciduous ginger. A plant arriving in the cooler months may be dormant with little visible top growth, which is normal and not a fault: keep it barely moist and it will shoot in spring. Plants are delivered Australia wide, with delivery from $29.95. Every plant is covered by our 30 day healthy plant guarantee.

Plant care guides and related reading

• Browse the wider edible plant range
• Find companions in our tropical garden plants
• Read the elephant ear care guide for the same warm season culture
• Match it to your region with plants for subtropical climates

Common questions

Why has my plant disappeared over winter?

Because it is deciduous. Black turmeric dies back to the rhizome each winter and reshoots in spring once the soil warms. Keep the soil almost dry while it is dormant.

Can I actually cook with it?

Yes. The rhizome is used in Indian cooking and is far more bitter and camphorous than common yellow turmeric, so it goes in sparingly. Harvest from your second or third season.

Will it grow in a pot?

Very well, in a pot 400mm or wider with rich mix and plenty of water through summer. Pots are also the practical answer outside the tropics and subtropics.