Aristolochia grandiflora aka Duckflower

Aristolochia grandiflora is a tropical climber called pelican flower. Other names include swan flower and poisonous hogweed. It belongs to the Aristolochiaceae family. Its native range spans southern Mexico and much of Central America. It also grows in the West Indies. In the wild, it lives in wet thickets and along streams. It grows among plants that return after land disturbance. Records place it up to 1,970 feet [600 metres] above sea level.

This strong-growing shrub climbs by means of twining stems. These reach at least 10 feet [3 metres] long. Useful Tropical Plants also lists a height of 49 feet [15 metres]. That figure does not establish its usual size in gardens. The plant uses nearby plants as supports as it climbs. It can spread over trees of medium size. Its climbing form matters when choosing a place to grow it. A small space may not suit a plant that covers trees.

The flowers are large, and the plant has an unpleasant smell. In tropical conditions, it can bloom throughout the year. It can also bear fruit across the year. These traits give it a long season of interest. Yet the smell may limit its appeal near seating areas. The supplied species account does not describe flower colour or fruit shape. Nor does it give species-level details of bark or leaf shape.

For cultivation, choose loam rich in humus that drains well. The plant accepts full sun or some shade. Its wild habitat places it in the warm lowland tropics. The evidence gives no frost limit or tested hardiness zone. Growers can raise it from seeds or softwood cuttings. Soak seeds in warm water for two days before sowing. Sow them on the surface of the growing medium. Germination works best at 25–30°C.

People gather wild plants for use in local traditional medicine. Reported root uses include snakebite treatment and attempts to induce menstruation or abortion. Traditional leaf uses include colds, chills, and promoting sweat. These reports do not establish safe or effective treatments. The roots have poisoned some mammals, according to the cited flora. No edible uses are recorded. The supplied evidence names no specific pests or diseases.