Sweet pepperCapsicum annuum

The pepper needs warmth from morning to night and a long season: in our climate, a greenhouse or polytunnel gives it both. Failing that, the foot of a south-facing brick wall, which radiates heat in the evening, is the warmest spot in the garden, provided it is closed to wind. The pepper is more compact than the tomato and is happy at the edge of the greenhouse, in front of the tomatoes, without getting in their way. Avoid where last year's tomatoes, aubergines or potatoes grew; they belong to the same family and share their diseases.

The pepper likes rich soil, but above all light and warm. In April, loosen the bed with a broadfork and work in three kilos of mature compost per square metre, with a handful of wood ash for potash. In clay soil, build a twenty-centimetre mound lightened with sand and compost: it drains and warms up faster. Cover the bed with black film or a dark mulch two weeks before planting to store heat. Do not add fresh manure or nitrogen fertiliser: you would get plenty of foliage and little fruit.

Sowing is done early, from mid-February to mid-March, but at first it needs more warmth than light: germination at 25 °C on a radiator or heat mat, then a south-facing windowsill or a grow lamp as soon as the seedlings are up. Allow three weeks to see the seedlings emerge; be patient. Favour early varieties or those with small elongated fruit, which turn red in August; the large square peppers often ripen too late in Belgium. If you have neither warmth nor light in February, buy plants in May: a wise decision, not a defeat.

A good plant is fifteen to twenty centimetres tall, with a thick stem and dark green foliage, sometimes a flower bud. Harden it off for a good week before planting out. Plant in a greenhouse from 20 May, outdoors not before 5 June, when the nights stay above 12 °C. Unlike the tomato, do not bury it deeper than it was in its pot, or the neck rots. Space at forty-five centimetres, water with tepid water and put in a sixty-centimetre stake. A fleece or cloche on the first cool nights avoids the check that costs weeks.

The pepper may be the fruiting vegetable best suited to a balcony, as a black pot against a warm wall gives it exactly what it wants. Allow twelve to fifteen litres per plant, a rich compost with a quarter of garden compost added and a drainage layer at the bottom. Place the pot facing south, sheltered from wind, and move it closer to the wall at night during cool spells. Water regularly without ever leaving water standing in the saucer; the pepper hates wet feet. A liquid tomato feed every ten days from flowering makes up for the limited volume. Dwarf varieties give small fruit in abundance.

Sowing late, in April, and watching the fruit arrive in October without ever turning red. Planting outdoors in mid-May: a cold night stalls the plant for three weeks and makes the first flowers drop. Overwatering for fear of drought, when the pepper prefers to dry out a little between waterings. Burying the plant deep like a tomato. Choosing a big supermarket variety rather than an early one suited to our summers. Forgetting the stake and finding the plant snapped by the weight of the fruit or a gust of wind. Losing patience in August: colouring still takes another three weeks.

The pepper prefers constant, moderate moisture. Water at the base twice a week in open ground, three times in full heat, giving two to three litres per plant, and wait for the surface to dry slightly before the next watering. In pots, check every day by pushing a finger into the compost. Too much water yellows the foliage and drops the flowers; too little causes blossom end rot on the fruit. Use water at room temperature, especially in the greenhouse, and water in the morning. Once the fruit starts colouring, reduce watering slightly: it will be sweeter and more fragrant.

Mulch only when the soil is properly warm, early June in a greenhouse, mid-June outdoors, as a mulch laid too early keeps the ground cold. Prefer a dark material, miscanthus mulch, dried grass clippings or leaf mould, five to eight centimetres deep. The pepper is a heavy consumer of potash: comfrey liquid diluted to 10 % every fortnight from the first flowers, or an organic tomato feed. A ring of compost in mid-July supports the fruit as it forms. Leaves that wilt despite watering or that lose colour between the veins often signal an excess of salts, not a deficiency.

Remove the first flower, the one that forms in the main fork: the plant then branches into three or four vigorous stems instead of exhausting itself on one early fruit. Tie the trunk to a sixty- to eighty-centimetre stake with a soft tie, and add ties on heavily laden branches in August. Remove the few leaves and shoots that appear below the fork to air the base of the plant. If a plant outdoors is carrying more than ten or twelve fruits, remove any new flowers after mid-August: they would come to nothing and delay the colouring of the fruit already formed.

The pepper is fairly healthy, provided you avoid excess water and stuffy conditions. In a greenhouse, ventilate every day from the morning and mist the soil in hot spells to discourage red spider mite, which turns the foliage greyish. Aphids lodge on the undersides of young leaves: a shower of soapy water with soft soap diluted to 5 % is enough, repeated three days apart. Slugs nibble fruit that touches the ground, hence the value of the stake. Grey mould on faded flowers is kept in check by removing them by hand. Practise a three-year rotation with the nightshade family to avoid wilt diseases.

Mid-February to mid-March: sowing at 25 °C, pricking out into pots at two true leaves. April: maximum light, sparing watering, first diluted feed. Mid-May: hardening off, planting in the greenhouse. Early June: planting outdoors, stake, cloche on cool nights, removal of the first flower. June: mulching, first comfrey feed. July: regular watering, ties, daily ventilation of the greenhouse, watching for aphids. August: first green fruit, removal of late flowers, reduced watering. September: colouring, main harvest. October: complete picking before the first frost, ripening of the last fruit indoors.

Pick with secateurs, keeping a centimetre of stalk, without pulling, as the branches snap. A full-sized green pepper is already good, but colouring brings the sugar: wait three more weeks if the season allows. Picking the first fruit green stimulates the plant and lets the following ones ripen better. In October, close the greenhouse in the evening and cover outdoor plants with fleece: two weeks gained. Before the first forecast frost, harvest everything, even the small fruit; the large green ones finish turning red within a week on the windowsill, next to an apple.