How to Grow Diamond Pepper
Wikimedia Commons
Diamond Pepper
Capsicum annuum
vegetableDiamond is a sweet bell pepper variety prized for its blocky shape, thick walls, and exceptional sweetness. It produces medium to large fruits that ripen from green to a brilliant red color, with outstanding flavor for fresh eating and cooking. This cultivar is known for its reliable production and disease resistance.
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Example Diamond Pepper timeline · Pittsburgh, PA (Zone 6b)
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Plant Diamond Pepper
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Diamond Pepper
Around Jun 26≈ 70 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Diamond Pepper dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 5-10; can be grown as an annual in zones 2-4 with proper protection
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Seedling
3-4 weeksTiny seedlings with true leaves emerging after the first cotyledons. Plants are fragile and small.
Provide bright light (14-16 hours), maintain warm temperatures (75-85°F), keep soil consistently moist but not soggy, and ensure good air circulation to prevent damping off.
Vegetative Growth
4-6 weeksPlant develops multiple stems and healthy green foliage. No flowers present yet. Rapid leaf and stem development.
Continue warm temperatures (70-80°F), provide full sun or grow lights 6-8 inches from seedlings, water regularly, and apply balanced fertilizer every 2 weeks. Pinch top early if leggy.
Flowering
3-4 weeksSmall white flowers appear at branch tips and leaf nodes. Flowers open and close daily.
Maintain consistent watering and temperature (65-75°F at night). Avoid temperature extremes below 55°F or above 90°F, which can cause flower drop. Fertilize with phosphorus-rich formula to support flowering.
Fruiting
4-6 weeksFlowers develop into small green peppers that gradually enlarge. Fruits ripen over time, changing from green to red.
Maintain even soil moisture (critical stage for fruit development), apply mulch to regulate soil temperature, provide stakes or cages for support, and switch to higher potassium fertilizer. Avoid overwatering.
Mature/Harvest
Ongoing until frost or plant exhaustionPeppers reach full size with thick, glossy walls and turn deep red. Plant may continue producing new flowers.
Harvest green peppers for faster production or allow to ripen to red for maximum sweetness and flavor. Continue watering and fertilizing to encourage continued production. Remove any diseased leaves.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Spray with neem oil or insecticidal soap weekly; increase humidity; remove heavily infested leaves; encourage beneficial insects.
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Spray water to dislodge; use insecticidal soap; apply neem oil; introduce ladybugs or parasitic wasps.
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Use sticky traps; spray neem oil or spinosad; remove affected foliage; maintain good air circulation.
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Use yellow sticky traps; spray neem oil or insecticidal soap; encourage parasitic wasps; avoid over-fertilizing with nitrogen.
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Remove infested fruits immediately; use pheromone traps; apply spinosad if needed; practice crop rotation.
Uses
Fresh Eating & Salads
CulinaryDiamond peppers are exceptionally sweet and crisp, making them ideal for fresh salads, crudités, and raw eating. Their thick walls hold up well when sliced. [source]
Grilling & Roasting
CulinaryThe thick walls and substantial size make Diamond peppers perfect for roasting whole or in large pieces over high heat, developing sweet caramelized flavors. [source]
Cooking & Stir-fries
CulinaryCook Diamond peppers in soups, stews, stir-fries, and fajitas where they retain color and texture. Red ripe peppers add visual appeal and natural sweetness to dishes. [source]
Preservation
HouseholdRed Diamond peppers preserve well through freezing, roasting and canning, or drying for future use in winter cooking. [source]
Vitamin C & Antioxidants
MedicinalRed Diamond peppers are rich in vitamin C and capsanthin (red pigment), supporting immune function and providing powerful antioxidant benefits. [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 green peppers 60-70 days after transplant for tender, crisp texture. For red, fully mature peppers with maximum sweetness, allow 80-90 days and wait until peppers turn deep red and feel firm. Use sharp pruners or scissors to cut peppers off the plant rather than pulling, which can damage branches. Harvest regularly to encourage continued production.
Fun Facts
- 🌱 Diamond peppers get sweeter the longer they stay on the plant—red fully-ripe peppers can contain up to 2.5 times more vitamin C than green peppers.
- 🌱 The variety name 'Diamond' reflects the pepper's exceptional quality and shiny, gem-like appearance when ripe.
- 🌱 Peppers are perennials in tropical climates but are grown as annuals in temperate zones. A single plant can produce 30-50+ peppers in a season under good conditions.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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