How to Grow Thai Long Green Chili

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Thai Long Green Chili

Capsicum annuum var. acuminatum

vegetable

Thai Long Green is a prolific chili pepper plant producing thin, elongated green peppers that are moderately hot and widely used in Southeast Asian cuisine. The peppers typically measure 3-4 inches long and transition from green to red as they mature. Known for their balanced heat and vibrant flavor, they're a staple in Thai cooking and curry pastes.

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Example Thai Long Green Chili timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Thai Long Green Chili

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Thai Long Green Chili

    Around Jul 16

    ≈ 90 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Thai Long Green Chili dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 8+ hours daily; prefer afternoon shade in extreme heat (above 95°F)
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Water: Keep soil consistently moist but not waterlogged; deep watering 2-3 times weekly during growing season; reduce frequency in cooler months
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Spacing: 18 inches
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Days to maturity: 90-150 days from transplant to first harvest
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Planting depth: 0.25 inches for seeds; transplant seedlings at true leaf stage

Soil

Type: Well-draining loamy soil with good organic matter
pH: 6.0-6.8
Amendments:
Compost aged manure peat moss or coconut coir perlite for drainage

Growing Zones

Find your zone →

Zones 9-11; can be grown as an annual in cooler zones with warm season extension

9a 9b 10a 10b 11a 11b

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Growth Stages

1

Seedling

3-4 weeks

Small plants with 2-4 true leaves; cotyledons still visible

Keep soil warm (70-80°F) and moist; provide bright light; thin to strongest seedling if direct sown; avoid overwatering to prevent damping off

2

Vegetative Growth

4-6 weeks

Bushy plant with increasingly thick stems and numerous leaves; no flowers yet

Maintain consistent warmth and moisture; fertilize every 2-3 weeks with balanced NPK; begin hardening off transplants; support with stakes if needed

3

Flowering

3-4 weeks

Small white flowers appear at leaf axils; plant reaches full height and width

Provide consistent warm temperatures (70-85°F); switch to lower-nitrogen fertilizer to promote flowering; ensure adequate pollination by light shaking; maintain even soil moisture

4

Fruiting & Development

4-6 weeks

Green peppers develop from flowers; peppers grow rapidly and increase in length

Continue regular watering and fertilizing; mulch to retain soil moisture and regulate temperature; thin crowded fruit if desired for larger peppers; watch for pests

5

Harvest

6-12 weeks of continuous harvest

Peppers reach 3-4 inches long; glossy green color indicates maturity; can continue ripening to red if left on plant

Harvest green peppers with pruners; continue harvesting to encourage more fruit production; reduce watering and fertilizing as season winds down in fall

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Fennel Kohlrabi Brassicas (cabbage, broccoli, cauliflower) Dill

Common Pests

  • Spray with water to dislodge; use neem oil or insecticidal soap; increase humidity; remove heavily infested leaves

  • Spray with strong water stream; apply insecticidal soap or neem oil; encourage beneficial insects like ladybugs; use yellow sticky traps

  • Remove infested leaves; use reflective mulches; spray with neem oil or spinosad; hang blue sticky traps

  • Remove and destroy infested fruits; use sticky traps; apply spinosad or pyrethrin; practice crop rotation

  • Use yellow sticky traps; spray with insecticidal soap or neem oil; vacuum adults with handheld device; encourage natural predators

Uses

🍳

Thai Curries & Pastes

Culinary

Thai Long Green peppers are essential ingredients in authentic Thai green curry pastes, where they're ground with garlic, lemongrass, and other aromatics. Their moderate heat and fresh flavor balance the creamy coconut milk in curries. [source]

🍳

Fresh Cooking & Stir-fries

Culinary

Use fresh green peppers sliced in stir-fries, pad thai, and other Southeast Asian dishes for a bright, spicy kick. They can be cooked whole, sliced, or minced depending on the dish. [source]

🍳

Pickled & Preserved

Culinary

Thai Long Green peppers preserve well when pickled in vinegar and salt brine, creating a condiment that lasts for months. They develop complex flavors during fermentation. [source]

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Capsaicin & Anti-inflammatory Benefits

Medicinal

The compound capsaicin in chili peppers has been studied for pain relief and anti-inflammatory properties. Regular consumption may support metabolism and cardiovascular health. [source]

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Natural Pest Deterrent

Household

Dried Thai Long Green peppers can be made into a spray to repel garden pests and insects. The capsaicin irritates many pest species while being safe for edible plants. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Harvest peppers when they reach 3-4 inches long and have a glossy bright green color, usually 60-90 days after flowering. Use sharp pruners or scissors to cut peppers from the plant to avoid damaging branches. For maximum heat and flavor development, allow some peppers to ripen to red on the plant. Regular harvesting encourages continuous production throughout the growing season. Peppers store well in the refrigerator for 1-2 weeks.

Fun Facts

  • 🌱 Thai Long Green peppers are the same species as sweet bell peppers but with a distinctly different appearance and heat level, demonstrating the incredible diversity within Capsicum annuum.
  • 🌱 In Thailand, these peppers are called 'Prik Kee Noo' (literally 'mouse dropping chili') due to their small, elongated shape, though the Thai Long Green is actually larger and milder than the bird's eye chili.
  • 🌱 The heat level can vary significantly based on growing conditions—peppers grown in hot, dry conditions with limited water tend to be considerably spicier than those with abundant moisture.

Gardening Terms

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