Winged/purple Yam

Winged yam is propagated from sections of tuber cut to include at least one bud, left to dry briefly before being planted horizontally a few inches deep and roughly two to three feet apart in loose, well-draining, loamy soil with a pH of about 5.5 to 7.0. A sturdy trellis or tree is needed from the start, since the twining vines can climb twenty to thirty feet, and the plant wants full to partial sun with shelter from strong wind.

Watering: Soil should be kept consistently moist through the growing season, with watering tapered off toward the end as the tubers bulk up, and mulch helps hold moisture. A balanced fertilizer applied regularly during active growth supports the vigorous vine, with feeding reduced as the plant enters its winter dormancy and the stems die back to the ground.

Winged yam is affected by root-knot nematodes and scale insects, along with aphids, spider mites, and other beetles that can trouble the climbing vine. Anthracnose and mosaic virus are diseases recorded on the crop, so gardeners are advised to watch for these alongside general pest pressure.

Tubers are ready to dig roughly six to ten months after planting, once the foliage begins to yellow and die back with the onset of dormancy. Digging must be done carefully around the base of the plant to lift the tuber without cutting or bruising it, since damaged tubers store poorly.

Storage: After lifting, tubers are cured in a warm, dry place for several days to toughen the skin, then kept in cool, dry conditions where they can last for months; storing in the ground or buried in sand is also used to hold tubers until the next planting.

Culinary: Winged yam is a staple tuber crop across Southeast Asia, the Pacific, and West Africa, most widely known in the Philippines as ube, where its purple flesh keeps its color after cooking and is used chiefly in desserts such as cakes, ice cream, and frappes rather than savory dishes. The tubers must be cooked thoroughly before eating, since the raw flesh is acrid and irritating.

Ornamental: Beyond the kitchen, the vine is grown for its vigorous climbing habit and large heart-shaped leaves, sometimes producing pale yellow to white flowers, making it a feature for trellises and arbors in tropical gardens.

Industrial: The plant's tubers contain the steroid diosgenin, historically used as a principal raw material in the manufacture of birth-control pills.

Winged yam traces its origins to the tropical regions of Asia and Oceania, though its exact wild origin remains unclear; it is considered a cultigen known only from cultivation and possibly a hybrid. Portuguese and Spanish traders carried it to the Americas in the 1500s, and it has since spread to become a staple crop in West Africa, South America, and the Philippines.