Peppers are tropical plants that need lots of heat and attention to detail when starting them. Well grown in a warm summer, they are the gardener’s triumph. Interestingly, the hot peppers often do better in a cool summer than the large bell peppers. If the hot peppers have not coloured up fully on your plants, pull up the whole plant and hang in a warm dry area. Follow along with this handy How to Grow Peppers from seeds guide and grow spicy and sweet delight.
Capsicum annuum, C. baccatum, and C. chinense
Season & Zone
Season: Warm season.
Zone: Not winter hardy. Grow in Zones 4 and up.
Peppers need plenty of time to mature before they will bloom and set fruit. Start indoors in early March to the first week of April under bright lights. Transplant only when weather has really warmed up in early June or later. Night time lows should be consistently above 12°C (55°F). Soil temperature for germination: 25-29°C (78-85°F). Seeds should sprout in 10 – 21 days.
Sow indoors 5mm-1cm (¼-½”) deep. Keep soil as warm as possible. Seedling heating mats speed germination. Try to keep seedlings at 18-24°C (64-75°F) in the day, and 16-18°C (61-64°F) at night. Before they become root-bound, transplant them into 8cm (3″) pots. For greatest possible flower set, try to keep them for 4 weeks at night, about 12°C (55°F). Then transplant them into 15cm (6″) pots, bringing them into a warm room at night, about 21°C (70°F).
Soil should have abundant phosphorus and calcium, so add lime and compost to the bed at least three weeks prior to transplanting. Mix ½ cup of complete organic fertilizer beneath each plant. Though peppers will tolerate dry soil, they will only make good growth if kept moist. Harden off before planting out in June, 30-60cm (12-24″) apart. Water in with kelp-based fertilizer. Using plastic mulch with a cloche can increase the temperature few degrees. Pinch back growing tips to encourage leaf production. this helps shade peppers and prevents sun-scald in hot summers.
When fruit is firm it is ready to pick. But if you wait the fruit will ripen further turning red, yellow, brown or purple. The sweetness and vitamin C content go up dramatically when the fruit changes colour. If you pick green the total numbers of peppers harvested will increase. Fruit that sets after late August will not usually develop or ripen. Pull out the entire bush just before the first frost and hang it upside down in a warm, dry place to ripen hot peppers. Expect 5-10 large bell peppers per well-grown plant, 20-50 hot peppers per plant.
In optimal conditions at least 65% of seeds will germinate. Usual seed life: 2 years.
Diseases & Pests
To prevent rot and wilt, plant in well-drained soils and follow a 4-year rotation.
If cutworms are a problem, use paper collars at the plant base. Tobacco mosaic virus (TMV): young growth is malformed and leaves are mottled with yellow. To prevent it: wash hands after handling tobacco, before touching peppers. Control aphids, which spread the disease.
Pepper plants make good neighbours for asparagus, basil, carrots, cucumbers, eggplant, endive, oregano, parsley, rosemary, squash, Swiss chard, and tomatoes. Never plant them next to beans, Brassicas, or fennel.