Growing Peppers

Peppers require a long growing season (60-150 days to harvest depending on variety) and warm soil to germinate. Start seeds indoors 8-10 weeks before last frost date. Hot peppers, especially superhots, germinate slowly - start these 10-12 weeks early. Sow 1/4 inch deep in sterile seed mix. Maintain soil temperature at 80-85°F for optimal germination (use a heat mat). Cool soil below 65°F results in spotty, slow germination.

Pepper seedlings are slow growers. Transplant into 3-4 inch pots when they have 2-3 sets of true leaves. Harden off for 10-14 days before outdoor planting - gradually expose to outdoor sun, wind, and temperature. Peppers are more cold-sensitive than tomatoes; do not transplant until nighttime temperatures consistently stay above 55°F.

Peppers want warm, well-drained soil with pH 6.0-6.8. Unlike tomatoes, do not bury pepper stems deeply - plant at the same depth as the nursery pot. Space sweet peppers 18-24 inches apart in rows 24-30 inches apart. Hot peppers can be spaced more closely (12-18 inches) as most are smaller plants.

Amend beds with compost and a balanced fertilizer. Peppers need moderate nitrogen (less than tomatoes), good phosphorus for fruiting, and ample potassium and calcium. Black plastic mulch or dark landscape fabric warms soil and speeds early growth in cool climates. In hot tropical climates, use light-colored straw mulch to keep roots cooler.

Most pepper plants benefit from staking, especially when loaded with fruit. A single bamboo stake or tomato cage prevents branches from snapping under heavy fruit loads. Bell peppers with 4-6 large fruits can become very top-heavy.

Pruning is optional but can increase yields in two ways: (1) Early flower removal - pinch off the first few flowers that form on transplants to redirect energy into root and foliage growth; this results in a larger plant that produces more fruit later. (2) Topping - for compact hot pepper plants, pinching the growing tip when plants are 8-12 inches tall encourages bushier growth with more fruiting branches. Commercial bell pepper growers generally do not prune; superhot growers often do.

Peppers need consistent moisture - 1-2 inches per week through drip irrigation. Water stress causes blossom drop, blossom end rot, and sunscald. However, peppers also dislike waterlogged roots. Mulch 2-3 inches deep to maintain even moisture.

Fertilize at transplant, then again when the first fruits appear, and every 3-4 weeks thereafter. Avoid high-nitrogen fertilizers - too much nitrogen produces large leafy plants with few peppers. Use a balanced or potassium-heavy feed (5-10-10 or 3-4-6). Calcium is important to prevent blossom end rot - add gypsum if soil calcium is low. Hot peppers stressed for water actually produce more capsaicin (hotter fruit), so some growers intentionally reduce watering as fruit ripens.

Capsaicin - the compound that makes peppers hot - is concentrated in the white pith and ribs inside the pepper, not the seeds (though seeds absorb it from contact). The Scoville scale measures heat: Bell peppers (0 SHU), Jalapeño (3,000-8,000 SHU), Serrano (10,000-25,000 SHU), Habanero (100,000-350,000 SHU), Carolina Reaper (1,400,000-2,200,000 SHU).

Growing conditions affect heat level: heat stress, drought stress, and higher temperatures increase capsaicin production. The same variety grown in a hot, dry climate will be hotter than one grown in a cool, well-watered garden. For maximum heat in superhot varieties, reduce watering as fruits approach maturity and grow in full sun with reflected heat (against a south-facing wall, in containers on pavement).

Sweet peppers: Harvest green bells anytime after they reach full size. For colored bells (red, yellow, orange), leave on the plant an additional 2-3 weeks until fully colored - flavor and nutrition improve dramatically. Use pruning shears to cut peppers; pulling can damage branches.

Hot peppers: Most hot peppers are harvested at full color (red, orange, yellow depending on variety). Jalapeños can be harvested green or left to turn red (red jalapeños are called "chipotles" when smoked). For drying, harvest fully ripe and string onto a line in a dry, well-ventilated area. Thin-walled varieties (cayenne, Thai, paprika) dry easily; thick-walled types (jalapeño, habanero) need a dehydrator or oven. Wear gloves when handling hot peppers - capsaicin oil on skin causes burning for hours.