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Trapa natans

Family Name: Trapaceae
Synonyms: Trapa bicornis Osbeck
Common Name: Water Caltrop, European Water Chestnut, Water Chestnut, Jesuits' Nut, 菱角, 欧菱, 红菱
Semi-Shade Lots of Water Fruit & Vegetable Ornamental Flowers Ornamental Foliage Aquatic &Hydrophyte


Family Name
Genus Epithet
Species Epithet
Name Status (botanical)
Common Names

Classifications and Characteristics

Plant Division Angiosperms (Flowering Seed Plants)
Plant Growth Form Aquatic & Hydrophyte (Floating, Emergent)
Lifespan (in Singapore) Perennial
Mode of Nutrition Autotrophic


Native Distribution Asia
Native Habitat Aquatic (Freshwater Pond / Lake / River)
Preferred Climate Zone Tropical

Description and Ethnobotany

Growth Form An annual aquatic floater. 
Roots Branch roots anchor plant
Foliage The plant produces linear, submerged and floating, rhombodial leaves with dentate margins which are arranged in rosettes up to 50cm in diameter. Each floating leaf has a petiole slightly filled with air to enable the leaves to float. 
Stems Spongy, cord-like stems provide buoyancy.
Flowers The flower is small and has 4 petals. 
Fruits Has 2 conspicuous, sharp pointed horns on opposite sides. The viable fruit turns greenish-brown when mature and will sink down into the soil. The old fruits are will instead, float to the surface and are not viable.
Habitat It is found in shallow, nutrient rich water bodies with still or slow-moving water. 
Cultivation It is ideally grown in a water pH of 6.0 to 7.2 and in water temperature of 18 to 28°C. 
Ethnobotanical Uses Edible Plant Parts (Edible Seeds)
Food (Fruit & Vegetable : The edible kernel has good starch content. In China, Japan and Korea, it is boiled, preserved in honey or used in local dishes. In India it is ground into flour. It is also eaten during the Chinese Mid-Autumn Festival. )
Medicinal ( Fruits of the Trapa natans plant have anti-inflammatory properties and are used in making liniments purportedly as a cure of elephantiasis, rheumatism, sores and sunburn. It is also said to have cancer-preventing properties.)

Landscaping Features

Desirable Plant Features Ornamental Flowers, Ornamental Foliage
Plant & Rootzone Preference - Tolerance Alkaline high pH Soils
Landscape Uses Pond / Lake / River
Thematic Landscaping Water Garden
Usage Hazard - Cons Invasive / Potentially Invasive

Plant Care and Propagation

Light Preference Semi-Shade
Water Preference Lots of Water
Potential Problems Vigorous growth, is a potential invasive weed in slow moving waters.


Foliage Retention Evergreen
Mature Foliage Colour(s) Green
Mature Foliage Texture(s) Smooth, Glossy / Shiny
Foliar Arrangement Along Stem Rosulate / Rosette
Foliar Shape(s) Non-Palm Foliage (Deltoid)
Foliar Margin Dentate
Foliar Apex - Tip Acute
Foliar Base Truncate / Square

Non - Foliar and Storage

Stem Type & Modification Herbaceous

Floral (Angiosperm)

Flower & Plant Sexuality 1 Bisexual Flowers
Flower Colour(s) White
Flower Grouping Solitary

Fruit, Seed and Spore

Mature Fruit Colour(s) - Angiosperms and Gymnosperms Brown
Mature Fruit Texture(s) Smooth
Fruit Type 1 Indehiscent Dry Fruit
Fruit Type 2 Nut / Nutlet
Mature Seed Colour(s) White
Seed Quantity Per Fruit Few (1-5)

Image Repository



Master ID 1236
Species ID 2529
Flora Disclaimer The information in this website has been compiled from reliable sources, such as reference works on medicinal plants. It is not a substitute for medical advice or treatment and NParks does not purport to provide any medical advice. Readers should always consult his/her physician before using or consuming a plant for medicinal purposes.
Species record last updated on: 13 November 2020.