Growing Chillies in Containers
Chillies might be the perfect container crop. They stay fairly compact, they love warmth, and a pot lets you give them exactly that: a sunny windowsill in spring, a warm patio in summer and a bright spot indoors when the weather cools. A single healthy plant can produce dozens of chillies, far more than most households can use fresh.
Quick answer
Grow one chilli plant per pot about 22 cm across, or three to a grow bag, in peat-free multi-purpose compost. Keep plants somewhere warm and bright: a greenhouse, conservatory or sunny windowsill, or outside against a sunny wall once nights stay above 12°C. Keep the compost evenly moist, and feed weekly with a high-potash liquid feed from the time the first flowers open.
Why chillies suit pots
Chillies come from warm climates and need more heat than the average British summer provides outdoors. Growing them in containers means you can:
start them indoors early in the year and keep them there until it's warm enough outside
move them into the sunniest, most sheltered spot as the seasons change
bring them back indoors in autumn to finish ripening, or even to keep them through winter
Many gardeners grow chillies in pots on a sunny windowsill all year, with no garden at all.
Choosing a variety
Compact, bushy varieties are easiest in pots, especially on a windowsill. The RHS recommends:
'Apache': a compact, reliable plant with hot chillies.
'Loco': a small, neat plant with medium-hot chillies, ideal for windowsills.
'Prairie Fire': a bushy plant covered in lots of small, very hot chillies.
Larger varieties also grow well in bigger pots, particularly in a greenhouse, but they'll need more room and support.
Container size
Chillies don't need huge pots. The RHS suggests one plant per pot about 22 cm across, or three plants to a standard grow bag. Compact windowsill varieties are happy in slightly smaller pots, while tall, vigorous varieties do better in something larger.
Move young plants up gradually rather than straight into a big pot. They grow best when their roots fill each pot before they move to the next size:
Seedlings: once they're 2–3 cm tall, move each into its own small pot or module.
Young plants: when roots show through the holes in the bottom, move them into pots about 13 cm across.
Final pot: once they've filled those, move them into their permanent 22 cm pot or grow bag.
Holes in the base are a must, as chilli roots hate sitting in water.
Compost
Use peat-free multi-purpose compost at every stage, from sowing to the final pot. For larger pots outdoors, mixing in some soil-based compost adds weight and helps stop tall plants blowing over. See best soil for vegetable gardening in the UK for more.
Sowing and timing
Chillies need a long growing season, so they're sown early, from late winter to mid-spring. Seeds need warmth to germinate, around 21°C, so a heated propagator or a warm windowsill is ideal. Once they're up, give them as much light as possible.
For sowing steps and dates, see when to plant chillies in the UK
Indoors or outdoors?
Indoors: a greenhouse, polytunnel or bright conservatory gives the best crops, but a sunny windowsill works well for compact varieties.
Outdoors: in milder parts of the UK, chillies can live outside once the nights stop dropping below 12°C, typically around the end of May or early June. Give them two or three weeks to adjust first, putting them out by day and bringing them in at night. Choose the warmest spot you have, ideally against a south-facing wall, and be ready to bring them in if the weather turns cold.
Chillies grow best above 15°C and can stop setting fruit in extreme heat above 30°C, so in a greenhouse, open the vents and door on hot days.
Watering
Keep the compost evenly moist, never soggy and never bone dry. In a sunny spot in summer, pots can need watering every day. The finger test works well: if the compost feels dry down to your first knuckle, it's time to water. In cooler weather, water less often, as waterlogged compost can rot the roots.
In a greenhouse, splashing the floor with water on hot days raises the humidity, which helps the flowers set and keeps red spider mite away.
Feeding
As soon as the first flowers appear, start feeding every week with a high-potash liquid feed, such as tomato feed. Chillies in pots rely on you for food, and regular feeding keeps them flowering and fruiting through the summer.
Pinching out and support
When plants reach about 30 cm tall, you can pinch out the growing tip. This makes them bushier with more, smaller chillies, although the first fruits will be a little later.
Tall plants laden with fruit can topple, so push a cane or two into the pot and tie the main stems in loosely.
Harvesting
In a greenhouse, the first chillies are usually ready in July, and picking continues into autumn. Plants outside tend to start a few weeks later, around August. You can pick them green or leave them to ripen to their final colour, which is usually red but can be yellow, orange or purple. Ripe chillies have a fuller flavour and are often hotter. Picking some green encourages the plant to produce more.
Cut the chillies off with scissors or secateurs rather than pulling them, as that can snap the brittle stems. See when to harvest chillies
Keeping chillies over winter
Because they're in pots, chillies can be brought indoors in autumn and kept over winter. Cut them back, put them on a bright, warm windowsill, and water sparingly until spring. An overwintered plant starts growing earlier the following year and often crops sooner than a new one.
Common problems
Aphids and whitefly: check under the leaves and wipe or wash them off.
Red spider mite: fine mottling on leaves and webbing in hot, dry conditions. Raise humidity and mist regularly.
Grey mould: fuzzy grey patches in cool, damp conditions. Improve ventilation and remove affected parts.
Flowers dropping: usually caused by a sudden temperature change, dry compost or dry air.
For more, see why chillies don't grow. Everything from sowing to harvesting is covered in how to grow chillies in the UK. Our container growing guide covers other crops in pots.
Common questions
What size pot do chillies need?
The RHS suggests a pot about 22 cm across for one plant, or three plants to a standard grow bag. Compact varieties can go in smaller pots.
Can chillies grow outside in pots in the UK?
Yes, in milder areas, once nights no longer drop below 12°C, typically from around the end of May. Put them against a warm, sunny wall and bring them in if it turns cold.
How often should I feed chillies in pots?
Once a week with a high-potash liquid feed, such as tomato feed, starting when the first flowers appear.
Can I keep my chilli plant over winter?
Yes. Bring it indoors in autumn, cut it back, and keep it on a warm, bright windowsill with just a little water until spring.
Pot sizes, temperatures, feeding and varieties based on RHS guidance.