Curcuma longa L.

Plants ca. 1 m tall. Rhizomes many branched, orange or bright yellow, cylindric, aromatic; roots tuberous at tip. Petiole 20--45 cm; leaf blade green, oblong or elliptic, 30--45(--90) × 15--18 cm, glabrous, base attenuate, apex shortly acuminate. Inflorescences terminal on pseudostems; peduncle 12--20 cm; spike cylindric, 12--18 × 4--9 cm; fertile bracts pale green, ovate or oblong, 3--5 cm, apex obtuse; coma bracts spreading, white and green, sometimes tinged reddish purple, apex acute. Calyx white, 0.8--1.2 cm, puberulent, apex unequally 3-toothed. Corolla pale yellow; tube to 3 cm; lobes deltoid, 1--1.5 cm, central one larger, apex mucronate. Lateral staminodes shorter than labellum. Labellum yellowish with central, yellow band, obovate, 1.2--2 cm. Anther spurred at base. Ovary sparsely hairy. Fl. Aug.

It is a tropical plant. It is widespread in coastal areas up to 1000 m altitude in the Philippines. It needs a hot moist climate and a well drained soil. The soil needs to be loose for good rhizomes. Plants can grow in the shade but the yield is lower. Plants are drought and frost tender. It needs a temperature above 13°C. It suits hardiness zones 10-11. In Sichuan and Yunnan.

The orange coloured rhizome is used as seasoning especially in curry. They are also used for food colouring. They can be used fresh or boiled and dried. The young shoots are also eaten. The flowers are roasted or fried and eaten.

Plants are normally grown from pieces of the rhizome. Pieces with one or two buds are used. Larger side tubers are best. They are planted 6-8 cm deep. The distance between plants needs to be 30-40 cm. They can also be grown from seed where these occur. The roots are harvested as the leaves start to die back.