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Trapa incisa

Trapa incisa
Educational content — not medical, botanical, or professional advice. Plant identification, safety, and edibility depend on local conditions, cultivars, and correct identification. Consult a qualified botanist or forager before consuming or handling wild specimens. How we source & review →
edibleannualannualedibleedible seedfull sunlight soilnative asia
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Trapa incisa (Trapa incisa) — botanical photograph
Pl. C6C0 — Trapa incisa
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Overview

Trapa incisa, commonly known as the water caltrop or Assam caltrop, is an annual aquatic plant native to regions including Assam, Cambodia, China, India, Japan, and Vietnam. This plant thrives in full sun and requires water for its growth, making it a distinctive feature of wetland areas. Trapa incisa is notable for its edible seeds, which can be harvested for consumption. The seeds are often prepared by roasting to enhance their flavor, making them a valuable food source in its native regions. This plant adapts well to various soil types, including light (sandy), medium, and heavy (clay) soils, making it versatile in diverse environments within its native range. Its annual life cycle and adaptability to different soil conditions contribute to its widespread presence across its native regions. While Trapa incisa is primarily known for its edible seeds, it does not have recognized medicinal uses.

Quick answers

What is Trapa incisa?

Trapa incisa, commonly known as the water caltrop or Assam caltrop, is an annual aquatic plant native to regions including Assam, Cambodia, China, India, Japan, and Vietnam. This plant thrives in full sun and requires water for its growth, making it a distinctive feature of wetland areas.

Growingconditions · propagation · uses
V

Cultivation

Trapa incisa thrives in full sun and requires ample water, making it suitable for aquatic or boggy conditions. The soil should be light to heavy but well-draining; sandy, medium, or clay soils are appropriate. This annual plant is native to regions across Asia and is hardy in temperate areas. For propagation, seeds can be used directly. Ensure the growing environment mimics its natural habitat for best results.
Light
Full sun
Water
Water
Soil
Light (sandy), Medium, Heavy (clay)
Life cycle
Annual
For first-time growers

How to grow Trapa incisa for the first time

8steps

Start with Trapa incisa as an annual in a container, focusing on basic care.

  1. 1

    What you'll need

    A container, seeds or seedlings, potting soil.

  2. 2

    Best time to plant

    Plant in spring after the last frost.

  3. 3

    Soil and container prep

    Use a well-draining mix suitable for aquatic plants. Ensure the container has drainage holes.

  4. 4

    Sowing or transplanting

    Direct sow seeds into the soil, covering them lightly. Alternatively, plant seedlings in the container.

  5. 5

    First two weeks

    Keep the soil consistently moist and provide full sun exposure. Monitor for signs of stress.

  6. 6

    Ongoing care

    Maintain water levels and ensure the plant receives plenty of sunlight. Repot if necessary as the plant grows.

  7. 7

    Harvest or pruning

    Prune any dead or damaged parts to encourage healthy growth. Harvest seeds when they are ripe.

  8. 8

    Common mistakes

    Overwatering, planting in non-draining containers, neglecting sunlight.

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Edible & utility

Edible parts:Seed
Edible uses: The seed of Trapa incisa is edible and can be consumed raw or cooked. It is often prepared by roasting to enhance its flavor. Skip
Contextrange · companions · related
VII

Distribution

17 native · 0 introduced
Distribution across1 continent· 17 native
Asia10 regions
native (10)CambodiaChinaIndiaJapanLaosMyanmarSouth KoreaTaiwanThailandVietnam
Broader regions
native:Hainan, Khabarovsk, Primorye
IX

Specimen gallery

1 image
Trapa incisa (Trapa incisa) — botanical photograph
Trapa incisa (Trapa incisa)
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Explore further

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About this entry

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