How to Grow Kew Red

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Kew Red

Capsicum annuum var. longum

vegetable

Kew Red is a distinctive long chili pepper variety known for its slender, elongated pods that mature from green to a deep red color. Originally developed at the Royal Botanic Gardens, Kew, this pepper offers moderate heat and a complex flavor profile suitable for both fresh use and cooking. The plants are compact yet productive, making them ideal for gardeners seeking an ornamental as well as functional pepper variety.

When should you plant Kew Red in your zone?

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Example Kew Red timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Kew Red

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Kew Red

    Around Jun 26

    ≈ 70 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Kew Red dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 8+ hours daily (more sunlight promotes better fruiting and pepper development)
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Water: Consistent moisture; water deeply 1-2 inches per week when soil is dry to 1 inch below surface. Reduce watering once peppers set to concentrate flavors. Avoid waterlogging.
📏
Spacing: 18 inches
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Days to maturity: 70-90 days from transplant to first red peppers
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Planting depth: ¼ inch for seeds; transplants at same depth as soil line

Soil

Type: Well-draining loamy soil rich in organic matter
pH: 6.0-6.8
Amendments:
Compost aged manure perlite or vermiculite for drainage balanced NPK fertilizer

Growing Zones

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Thrives in zones 6-10; can be grown in cooler zones with season extension techniques

3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a

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Growth Stages

1

Seedling

2-3 weeks

Tiny seedlings with first true leaves emerging; plant appears delicate with cotyledons fading

Maintain consistent warmth (70-80°F). Provide bright light 14-16 hours daily. Keep soil moist but not waterlogged. No fertilizer yet.

2

Vegetative

4-6 weeks

Plant develops multiple branches and leaves; robust growth with no flowers yet; stems become woody and stronger

Begin light fertilizing every 2 weeks with balanced NPK (14-14-14). Ensure full sun exposure. Pinch top when 6 inches tall to encourage branching.

3

Flowering

2-3 weeks

Small white flowers appear at leaf axils along branches; plant may set many flower buds

Maintain consistent watering. Switch to higher phosphorus fertilizer (5-10-10) to support flowering. Ensure good air circulation. Avoid over-nitrogen which reduces flowers.

4

Fruiting

3-4 weeks

Green peppers develop and elongate; pods grow to 3-4 inches long with slender, pointed shape characteristic of Kew Red

Continue consistent watering and fruiting fertilizer. Support heavy fruit with stakes if needed. Reduce nitrogen. Mulch to regulate soil temperature and moisture.

5

Maturation to Red

2-3 weeks

Peppers mature from green to vibrant deep red; final size and heat development; full color transition indicates peak ripeness

Allow peppers to remain on plant for full red color development (2-3 weeks from green). Reduce watering slightly to concentrate sugars. Protect from heavy rain or wind.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Fennel Kohlrabi Brassicas (when young) Apiaceae family herbs at high density

Common Pests

  • Spray with water; use insecticidal soap or neem oil; introduce ladybugs; reflective mulch

  • Increase humidity; mist plants regularly; spray neem oil; isolate heavily infested plants

  • Yellow sticky traps; insecticidal soap; neem oil; reflective mulch; avoid excess nitrogen

  • Row covers on young plants; diatomaceous earth; spinosad spray; neem oil

  • Remove infested fruit immediately; use pheromone traps; spinosad spray; practice crop rotation

Uses

🍳

Fresh Use and Cooking

Culinary

Kew Red peppers are excellent for fresh salads, salsas, and stir-fries. Their slender shape makes them suitable for stuffing or roasting whole. The moderate heat (5,000-30,000 Scoville units) provides flavor without overwhelming heat. [source]

🍳

Pepper Flakes and Dried Goods

Culinary

Mature red Kew Red peppers dry exceptionally well for creating homemade pepper flakes or chili powder. The thin-walled structure allows for quick drying. [source]

💊

Capsaicin and Health Benefits

Medicinal

Red peppers contain capsaicin, a compound studied for anti-inflammatory and pain-relief properties. They are also rich in vitamin C and antioxidants. [source]

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Ornamental Garden Feature

Household

Kew Red's compact growth habit (12-18 inches tall) and progression from green to red peppers makes it highly ornamental. Suitable for container gardening on patios and balconies. [source]

🎨

Seed Saving

Craft

Kew Red is a stable open-pollinated variety ideal for seed saving. Ripe red peppers can be harvested, fermented, dried, and their seeds saved for future seasons. [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 at green stage for milder flavor (after 70 days), or wait 2-3 additional weeks for full red maturity with deeper, spicier flavor. Use pruning shears or sharp knife to cut peppers; do not pull. Regular harvesting encourages continuous production. Each plant produces 20-40+ peppers per season.

Fun Facts

  • 🌱 Kew Red was developed at the Royal Botanic Gardens in Kew, London, and was selected specifically for its ornamental qualities combined with culinary value.
  • 🌱 Chili peppers are technically berries botanically, and a single Kew Red plant can produce over 40 peppers in a season if grown in optimal conditions.
  • 🌱 The heat level of Kew Red peppers increases as they mature and turn red; green peppers from the same plant are noticeably milder than their red counterparts.

Gardening Terms

New to gardening? Learn about terms used in this guide:

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