Chilli pepper

Growing your own chilli peppers means you can choose from a huge array of colours, shapes, flavours and levels of heat – a much wider range than you can buy in supermarkets. Chillies are easy to grow in pots in a greenhouse or, after starting off indoors, can be grown outdoors in a warm sunny spot.

Jobs to do now

  • Water well, especially when dry
  • Feed every two weeks with a general purpose fertiliser
  • Harvest fruit as it ripens

Month by month


Sow indoors from late winter to mid-spring – an early start will give you an earlier crop.

Fill a small pot with seed compost, firm gently then sow a few seeds on top. Most seeds will germinate, so only sow a few more than you need, in case of losses. Cover with a fine layer of vermiculite, pop in a plant label and water.

Seeds will germinate quickly in a heated propagator, or simply put the pots on a warm sunny windowsill. Place a clear plastic bag over each pot, secured with an elastic band, to raise the humidity.

As soon as seedlings appear, take the pot out of the propagator or remove the plastic bag. 

When seedlings are 2.5cm (1in) tall, move each one into its own small pot filled with multipurpose compost. Water and keep in a warm sunny spot indoors.

If you don’t have time to sow seeds, or don’t have a suitably warm, bright place to raise good plants, then buy young chilli plants from garden centres in late spring.


While plants are still growing indoors, move them into larger 13cm (5in) pots when roots begin to show through the drainage holes in the base.

When they reach about 20cm (8in) tall, or if they start to lean, stake with a thin cane.

Pinch out the shoot tips when plants are about 30cm (12in) tall to encourage lots of branches, which should give you more fruit.

By late May, move each plant into its final 22cm (9in) pot or plant three in a standard growing bag. Keep these in a greenhouse or move them outside when all danger of frost has passed. Alternatively, plant them into the ground, spaced 45cm (18in) apart. Give them a warm, sheltered, sunny spot, and cover initially with fleece or cloches.

Support tall or top-heavy plants by tying loosely to a bamboo cane.

For a bumper crop, water regularly, especially in hot weather, and feed every two weeks with a general purpose liquid fertiliser. Feeding should start when the flowers first appear, usually while plants are still indoors, and should continue until the fruits have all been harvested.

Common problems


Look for colonies of greenfly on the soft shoot tips of plants or on leaves. They suck sap and excrete sticky honeydew, encouraging the growth of black sooty moulds.


Use your finger and thumb to squash aphid colonies or use biological control in the greenhouse.


Small white flies suck sap and excrete sticky ‘honeydew’ over the plant, encouraging the growth of sooty mould.


Use biological control or sticky traps in the greenhouse.

Grey mould
Grey mould

A usually grey, fuzzy fungal growth which can begin as pale or discoloured patches. Grey mould ( botrytis) is a common disease especially in damp or humid conditions. Spores enter plants via damaged tissue, wounds or open flowers. Mould can also damage ripening fruit such as strawberries. Black resting spores survive over winter.


Remove damaged plant parts before they can become infected. Cut out infected areas into healthy tissue and clear up infected debris. In greenhouses, reduce humidity by ventilating and avoid overcrowding of young plants and seedlings.


Chilli peppers are generally ready for harvesting from mid-summer, and will continue fruiting well into autumn if grown in a greenhouse.

Picking regularly, using a sharp knife or secateurs, encourages plants to produce more fruit. Leaving chillies to ripen fully (usually to red) will suppress further fruit production. But that can’t be avoided if you want the richest colour and flavour, and the best fruits for drying.


Nigel Slater uses chillies in his delicious spiced pork patties in lettuce leaves.

Recommended Varieties

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