How to Grow Chillies and Peppers (Capsicum annuum)

This is a fantastic crop for you to grow at home. Both pepper types produce bright peppers that give the windowsill or containers an exotic touch. And the flavoursome sweet or hot peppers make a great ingredient for kitchen recipes.

When and how to sow:

If sowing chillies and peppers from seed, they need to be sown from February to April in the UK. Sow chillies and pepper seeds in pots in March for an outdoor crop, or mid-February for an indoor crop.

Sow two seeds per pot and remove the weaker seedling about a month later as they grow.

When growing chillies and peppers from plants they need to be planted in May. Before planting outside, makes sure to harden the plant off by bringing it inside in the evening on cool nights and leaving outdoors during the day.

Indoor plants are susceptible to the red spider mite, so be sure to keep indoor plants well misted to keep this pest at bay. Misting also raises humidity levels which will encourage fruit set (the process of flowers becoming fruit and when the potential fruit size is determined).

Peppers may need to be re-potted several times until they go into their final position, as they grow rapidly once they get started.

They are happy to be grown in pots or containers, there are plenty of types available to choose from such as ‘Dwarf types’ which are perfect for growing on a windowsill if you don’t have a greenhouse. We recommend ‘Basket of Fire’ for a compact plant that produces a high number of fruits. 

Varieties of peppers and chillies:

Chillies and peppers vary wildly from being incredibly hot to very sweet, with many variants in-between:

Sweet Peppers: Different varieties of sweet pepper grow to reach different sizes:

  • ‘Dwarf’ or ‘compact’ plants are bushy and grow to around 25cm tall
  • Non dwarf varieties can grow to between 60 and 100cm tall

The fruit of sweet peppers vary in shape, size and colour from variety to variety, shapes include conical, square and bonnet-shaped, and colours include green, yellow, orange, purple and white. 

Chilli Peppers: Available in dwarf form as well as tall, ranging in different flavours and hotness, there’s plenty to choose from and all are quite unique.

  • Chilli peppers are easier to store than sweet peppers. Often, the plants provide too many chillies to eat in a season, which is why it's useful to be able to store them for use later
  • Some varieties are suitable for drying, such as Cayenne, and others can be preserved in oil, pickled or frozen. If you're going to freeze them, be aware that they go very soggy once they've defrosted so it's best to use them chopped up in recipes.

Planting Peppers and Chillies

Plant outdoors in late May/Early June in containers or in the ground with protection such as cloches or horticultural fleece until well into summer.

If growing more than one plant in open ground, space at 45cm (1 ½ ft) apart.

Feeding Peppers and Chillies

Provide both sweet and chilli peppers with a soil added with general purpose fertiliser. At fruiting provide a potassium-rich feed such as tomato feed with each watering.

Watering Peppers and Chillies

Regular misting is advised to keep red spider mite at bay, especially when growing under glass. Keep crops well-watered but be mindful not to have the soil sodden.

What temperature to grow Peppers and Chillies in

Grow peppers and chillies in a sunny and sheltered site if outdoors, and be sure not to expose plants, especially when young, to cold conditions or drafts.

When raising seedlings indoors, ensure an ambient temperature of 15-20C (60-70F).

Caring for chillies and peppers while growing:

The plants will naturally branch out unaided, so don’t be tempted to pinch the tips of the plant outwards. Only pinch out the tips as a last resort if the plant is growing spindly or is reluctant to branch.

To keep your plant growing in a bushy shape and to encourage the growth of more fruit, cut off the growing tip of the stem (just above a branching point) once it reaches about 35cm tall. The growing tips can also be pinched out of the branching stems as well to encourage even more fruit.

If the plants become heavily laden with fruit the branches may require a little bit of support from a small cane or stake.

For best results, once plats are established feed once every two weeks with Bio-Gro Black Gold or Tomato Plant feed. This will encourage the plants to produce as many chillies or peppers as possible.

Keep chilli and pepper plants moist, but try not to over water – they don’t like to sit in water for long periods of time. They enjoy high humidity, which can be achieved by watering the floor of the greenhouse or leaving trays of water next to the plants. Where the plants are grown under cover, keep them well ventilated. If possible, spray or mist the foliage with water every day.

Harvesting and Storing Peppers and Chillies

Chillies and peppers grown from seed will be ready to harvest from July to October. While chillies and peppers grown from plants will be ready during July to September.

Harvest chilli and sweet peppers when they are still slightly immature. This will encourage further fruiting. Pick green sweet pepper when they are smooth and glossy. Peppers may take up to two weeks to mature, and longer if it’s a dull summer.

Best varieties of Peppers and Chillies

At Marshalls we stock a range of pepper and chilli varieties, here’s what we recommend:

Sweet pepper ‘Snackbite’: Tender and crisp, with an excellent super sweet flavour

Chilli ‘Norfolk Naga’: Hits 1 million plus on the Scoville chart for chilli heat – so is definitely not for the faint-hearted!

Chilli ‘Jalapeno’: The original fiery chilli pepper. The 2in/5cm, plump and glossy green fruits (later red) are freely produced on short, branching plants.

Pests and Diseases of Peppers and Chillies

Red spider mite, Aphid, Whitefly

Health Benefits of Chillies and Peppers

Peppers a packed full of vitamins A, C and K which support the immune system and cells. They’re full of antioxidants too. Chillies contain capsaicin which could reduce cholesterol and also help reduce the risk of stomach ulcers.