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Trapa natans
Also called Water chestnut, Jesuit's nut, European Water Chestnut, Water Nut, Bullnut, Common Water Chestnut, Water Nut, Horn Nut
Water caltrop is a floating annual aquatic plant grown for its edible seeds, with leaf rosettes on a rooted stem in shallow, slow-moving fresh water. Warm, sunny, nutrient-rich water is the key to growing it.
Trapa natans, the water caltrop, is a widespread species of flowering plant in the genus Trapa, family Lythraceae, grown as a food crop. Other vernacular names include buffalo nut, bat nut, devil pod, ling nut, mustache nut, singhara nut, water nut, and water chestnut, though this last name is commonly applied to Eleocharis dulcis.
It is a floating annual aquatic plant, growing in slow-moving freshwater up to 5 metres (16 feet) deep, native to warm temperate parts of Eurasia and Africa. It bears horned fruits. Each fruit contains a single large seed. T. natans has been cultivated in China and the Indian subcontinent for the edible seeds for at least 3,000 years.
The habitat of Trapa natans is shallow, slow-flowing fresh water with bottom mud. The species prefers warm, nutrient-rich and sunny areas; the bottom is usually soft and rich in organic matter. It requires water temperatures to be above 22 °C (72 °F) for at least 2 months per year, and is expanding its range northwards due to climate change.
Text excerpted from the Wikipedia article Water caltrop by its contributors, under CC BY-SA 4.0; the excerpts and the care summary drawn from them are shared under the same licence.
The care summary was written by AI (Claude, Anthropic) from the sources on this page, with general growing knowledge where they are silent. Check before relying on it.
Life form, climate and native range: World Checklist of Vascular Plants, Royal Botanic Gardens, Kew (CC BY 3.0), reformatted; see Plants of the World Online.
