Chilli Pepper

Sow chilli seeds indoors in late winter or early spring, as they need a long season. Fill pots or trays with moist, peat-free compost and sow seeds about 0.5 cm deep. Cover lightly with compost and water. Keep them at around 21 °C in a propagator or warm spot for germination (which takes 1–3 weeks). Make sure the compost stays damp until seedlings emerge.

When the seedlings develop their first true leaves, transplant each one into its own small pot (around 8 cm). Handle seedlings gently by a leaf when lifting them. Keep the young plants in a bright place at 16–18 °C and water as needed to maintain moist compost. You may need to pot them on again into a slightly larger pot before moving them to the greenhouse.

Move your chilli plants into the greenhouse once they are well established and the weather is mild. This is usually around the time of the last frost in your area. Plant each chilli into its final container (about 22 cm pots or larger) or a greenhouse border. Ensure nighttime temperatures in the greenhouse stay above 10 °C to prevent a check in growth. Water the plants after transplanting and provide support canes if the variety is tall.

As the season warms up, open greenhouse vents or doors on sunny days to prevent overheating (above 30 °C). Chilli flowers are self-pollinating, but gently shaking the plants or using a soft brush can help spread pollen, especially in a still air environment. Good ventilation and occasional hand-pollination will help ensure a good fruit set and healthy plants in the greenhouse.

Once the chilli plants start flowering, begin feeding with a high-potash liquid fertiliser (like tomato feed) every week or so. Greenhouse chillies often grow quickly, so regular feeding and watering is essential to support the abundant fruit development. Avoid letting plants dry out; consistent moisture will prevent flower drop and improve yields.

Greenhouse-grown chillies often ripen a bit earlier, so you may start picking your first peppers by June. Harvest once fruits are firm and coloured (or even when green, if you prefer milder flavour). Continue picking regularly throughout the summer. In a warm greenhouse, even the hottest varieties can ripen fully by late season (around August). Use scissors to cut peppers from the plant to avoid breakages.