Growing Sweet pepper

Sweet peppers and chillies are botanically the same plant. When we say peppers, we usually mean the mild, non-hot vegetable peppers, such as bell peppers or sweet pointed peppers.

Together with chillies and aubergines, they need more warmth than any other crop and have a very long growing season. That is why they hardly suit growing outdoors, except in areas with a wine-growing climate. Hardy, early-ripening varieties from Hungary and the Balkans still do well in beds in cooler areas, and you can grow others in pots in a sheltered spot on a balcony or patio.

Start your peppers indoors, as direct sowing in the bed doesn't work in our climate. Sow from early to mid-March, about eight to ten weeks before the last frosts, or from mid-February for the greenhouse. The seeds germinate best at 25 °C. Below 20 °C they germinate slowly or go mouldy.

After about three weeks, prick out the seedlings a little deeper into their own pots and keep them in a bright spot at 20 to 22 °C. Once well hardened off, plant them outdoors after mid-May, 40 to 50 centimetres apart, or in the greenhouse from late April.

With sweet peppers and chillies, it depends on the variety whether the seeds need light or darkness to germinate. Most germinate in the dark.

Sweet peppers need lots of warmth and light. They grow best in a greenhouse, in a polytunnel or against a sunny, sheltered house wall. The soil should be deep, rich in humus and loose. Peppers cope badly with waterlogging and compacted soil. Below 15 °C the plants drop their flowers, and below 10 °C they stop growing. In a container with 10 to 20 litres of soil they do well on a balcony or patio, because the roots warm up faster there.

With peppers, you can tell apart the mild vegetable peppers, such as thick-walled bell peppers, cone-shaped wax peppers, pointed peppers and tomato peppers, from the long pepperoncini and the hot chillies, which have their own plant page. For growing outdoors in cooler areas, choose early-ripening, thinner-walled varieties from Hungary, the Balkans and Burgenland, such as ‘Roter Augsburger’. For the greenhouse and containers, you can find pepper varieties resistant to viruses and verticillium wilt.

Don't give peppers all their fertiliser at once, feed them bit by bit: put well-rotted compost in the planting hole and, once the fruits set, give a small dose of plant liquid feed every one to two weeks. Too much nitrogen means leaves instead of fruit and encourages blossom end rot. Water generously and evenly, a thorough soak twice a week rather than a little every day, and never let the soil dry out completely. In cool areas, pinch out the first flower in the fork of the stem so the plant can grow strong first. Tall varieties need a cane or strings, and outdoors a fleece protects them on cold nights.

Outdoors, sweet peppers have few problems, but under glass you need to keep a closer eye on them. Aphids are the most common pest, especially the peach-potato aphid. They like to turn up when plants get too little light or too much nitrogen. Keep enough space between plants and spray early with a soft soap solution if you spot them. In the greenhouse, heat and dry air bring red spider mite, thrips and whitefly as well. Humid air and beneficial insects keep them in check.

Aphids also spread viruses such as cucumber mosaic virus. Young pepper leaves then become mottled, crinkled or blistered, and the plants stay small. Viruses can also hide in seed and in tobacco, so wash your hands after smoking.

In mid and late summer, caterpillars of the European corn borer, cabbage moth and tomato moth eat holes in the fruits. Pick them off. Sweetcorn next to the peppers helps against the corn borer.

If your peppers wilt from the bottom up and the vessels in the stem are brown, verticillium wilt is usually to blame. Remove diseased plants and leave four years before growing any nightshade family crop there again. Brown, sunken patches at the tip of the fruit aren't a disease but blossom end rot, caused by uneven watering and heat.