When to plant Sweet Peppers in London

Capsicum annuum

Sweet Pepper
Sweet Pepper · Capsicum annuum

Sweet peppers are tender annuals that produce crisp, colourful fruits with a mild flavour. Native to Central and South America, they thrive in warm, sunny positions and are commonly grown under glass in the UK to ensure reliable cropping, though they can succeed outdoors in sheltered spots during particularly warm summers.

75 cm · Full Sun · Moderate Water

Add to garden

Calibrated to London · average last frost around 4 Apr

Sow indoors January, plant out May, harvest June to August. Typical frost risk November to April.
ActivityJanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember
Sow indoorsYesNoNoNoNoNoNoNoNoNoNoNo
Plant outNoNoNoNoYesNoNoNoNoNoNoNo
HarvestNoNoNoNoNoYesYesYesNoNoNoNo

Growing guide

What to do through the growing season

Growing guide for

Change the guide to see different planting timelines and tips.

Step by step guide to growing sweet peppers outdoors in a warm, sheltered spot.

  1. 01

    Sow Seeds Indoors

    4 Jan to 24 Jan

    Fill seed trays with peat-free seed compost and sow seeds about deep around 4th January - 24th January. Cover lightly and water gently from below. Keep on a warm windowsill or in a propagator at .

  2. 02

    Prick Out Seedlings

    6 Jan to 8 Feb Dates as each sowing reaches this stage

    When the first true leaves appear, transplant seedlings into pots with peat-free compost. Keep in a bright, warm spot and water to keep moist.

  3. 03

    Pot On

    27 Jan to 3 Mar Dates as each sowing reaches this stage

    As plants grow and roots fill the pots, move them to larger containers to develop strongly before planting out.

  4. 04

    Harden Off

    21 Apr to 4 May

    Harden plants off over 21st April - 4th May. Put them outside in a sheltered spot during the day and bring them in at night, gradually increasing exposure over about two weeks.

  5. 05

    Transplant Outdoors

    1 May to 15 May

    After all risk of frost has passed, plant in a sunny, sheltered spot with well-drained soil. Space apart and stake if needed. Protect from slugs with barriers.

  6. 06

    Pinch Out Growing Tips

    11 May to 8 Jun Dates as each sowing reaches this stage

    Pinch out the tips when plants are high to promote bushiness and more fruits.

  7. 07

    Fertilise

    11 May to 23 Aug Dates as each sowing reaches this stage

    Once flowers form, feed every week with high-potash fertiliser. Water consistently and mist flowers in dry weather to aid fruit set.

  8. 08

    Harvest

    20 Jun to 28 Aug Dates as each sowing reaches this stage

    Harvest when fruits are full-sized, picking green or allowing to colour for sweetness. Keep picking to extend the crop.

Suggested varieties

Popular varieties of Sweet Pepper to consider

California Wonder

A classic blocky bell pepper with thick, crisp flesh and a sweet flavour. It's a reliable cropper in UK greenhouses and also does well in a sunny, sheltered spot outdoors.

Gypsy

An early-maturing sweet pepper with elongated, pointed fruits that ripen from pale green to red. It's productive in cooler summers and is well-suited to growing in pots on a patio or in a greenhouse.

King of the North

A heritage variety bred for short, cool seasons, producing blocky fruits that ripen to a deep red. It copes with variable UK weather better than many bell peppers, making it a good choice for outdoor growing.

Marconi

An Italian-style sweet pepper with long, tapering fruits that are sweet and juicy. It's vigorous and heavy-cropping, and the thin walls cook down quickly, though it's also good eaten fresh in salads.

Ariane

A modern orange bell pepper that ripens early and consistently, even in cooler conditions. The fruits are sweet and crunchy, and the plants stay compact, so they suit smaller greenhouses or large containers.

Sweet Pepper guides by town

See how Sweet Pepper timing shifts in other towns with different frost dates.