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Sweet Trefoil

Trigonella caerulea
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Trigonella caerulea (Sweet Trefoil) — botanical photograph
Pl. 05FC — Trigonella caerulea
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I

Overview

Sweet Trefoil, scientifically known as Trigonella caerulea, is an annual herb native to Greece. This plant thrives in full sun and prefers moist conditions, growing up to 0.6 meters tall. It is both edible and medicinal, making it a versatile addition to gardens and landscapes. The leaves are the primary edible part used for culinary purposes, such as in condiments and teas. Sweet Trefoil has been documented for its medicinal uses, contributing to its value in traditional practices. Its adaptability to various soil types, including light (sandy), medium, and heavy (clay), makes it a suitable choice for gardeners interested in both ornamental and practical benefits. While it is not drought-resistant, consistent moisture is essential for optimal growth. Sweet Trefoil is native to Greece and has been introduced to several regions, including the Baltic States, Belarus, Bulgaria, and parts of China and Europe. Its distinctive features include its light requirement and its ability to fix nitrogen in the soil, making it a valuable nitrogen-fixer in agricultural settings.

Quick answers

What is Sweet Trefoil?

Sweet Trefoil, scientifically known as Trigonella caerulea, is an annual herb native to Greece. This plant thrives in full sun and prefers moist conditions, growing up to 0.6 meters tall. It is both edible and medicinal, making it a versatile addition to gardens and landscapes.

IV·b

Mixology suggestions

1 draft
Editorial drafts. These pairings are AI-suggested from traditional herbal lore. Always verify with a qualified herbalist before brewing.
Digestive Harmony
digestion
tincture
Historically used for digestive issues.
Growingconditions · propagation · uses
V

Cultivation

Sweet Trefoil thrives in full sun and prefers moist, well-drained soil that can be light (sandy), medium, or heavy (clay). This annual plant grows to about 0.6 meters and is easy to cultivate. For best results, keep the soil consistently moist. Propagate Sweet Trefoil by direct seeding in the garden. Harvest the leaves for culinary use. The plant is hardy in temperate regions and is native to Greece.
Light
Full sun
Water
Moist
Soil
Light (sandy), Medium, Heavy (clay)
Life cycle
Annual
Habit
Forb/herb
Mature size
0.6 m tall
For first-time growers

How to grow Sweet Trefoil for the first time

8steps

Sweet Trefoil is a straightforward annual herb for beginners to grow.

  1. 1

    What you'll need

    Seeds, small pots or garden space, potting soil.

  2. 2

    Best time to plant

    Plant in spring after the last frost, when temperatures are mild.

  3. 3

    Soil and container prep

    Use well-draining soil with a mix of light (sandy), medium, or heavy clay soils. Ensure containers have drainage holes.

  4. 4

    Sowing or transplanting

    Start seeds indoors 4-6 weeks before the last frost date, then transplant outdoors once seedlings are strong and weather is warm.

  5. 5

    First two weeks

    Water regularly to keep soil moist but not waterlogged. Place in a sunny spot to encourage growth.

  6. 6

    Ongoing care

    Provide full sun exposure and regular watering, especially during dry spells. Pinch back stems to promote bushy growth.

  7. 7

    Harvest or pruning

    Prune regularly to maintain size and shape, cutting back by one-third at a time. Leaves can be harvested throughout the growing season.

  8. 8

    Common mistakes

    Overwatering, planting in heavy shade, neglecting regular pruning.

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Edible & utility

Edible parts:Leaves
Edible uses: Condiment, Tea
Other uses:Nitrogen fixer
Contextrange · companions · related
VII

Distribution

1 native · 19 introduced
Distribution across2 continents· 1 native· 19 introduced
Europe6 regions
native (1)Greece
introduced (5)BelarusBulgariaRussiaUkraineUnited Kingdom
Asia2 regions
introduced (2)ChinaMongolia
Broader regions
introduced:Baltic States, Czechoslovakia, Maryland, New York, Primorye, Transcaucasus
IX

Specimen gallery

1 image
Trigonella caerulea (Sweet Trefoil) — botanical photograph
Sweet Trefoil (Trigonella caerulea)
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Native to
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