RHS Growing Guides
Our detailed growing guide will help you with each step in successfully growing Peppers.
1
Getting Started
Section 1 of 8
With their colourful fruits, sweet peppers are a vibrant and attractive crop. Also known as bell peppers or pointed peppers, depending on the fruit shape, these tender plants are best grown in a greenhouse, but can also be planted outdoors in a sunny spot, in pots or in the ground.
Peppers can be picked at any stage â when green and crunchy or when riper and sweeter
A cloche is a small, portable, protective structure made of glass or rigid transparent plastic used to protect plants, especially overwintered and early vegetables, from wet and cold weather and to warm the soil before planting.
Transparent fleece and other floating films, known collectively as crop covers, are laid over or around plants hastening their growth, and protecting against weather and pests. They are usually used without supporting hoops.
Closely related to chillies, they make attractive plants with their colourful, glossy fruits, which ripen from mid-summer to early autumn. They also take up little space, usually reaching only about 60cm (2ft) tall and 30cm (1ft) wide, and grow well in large pots.
Month by Month
Jobs to do now
- Sow seed indoors
- Sow seed indoors
| J | F | M | A | M | J | J | A | S | O | N | D | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sow | N | Y | Y | Y | N | N | N | N | N | N | N | N |
| Plant Out | N | N | N | N | Y | Y | N | N | N | N | N | N |
| Harvest | N | N | N | N | N | N | Y | Y | Y | Y | N | N |
2
Choosing
Section 2 of 8
Compact varieties such as âMohawkâ are ideal for growing in containers
Some varieties are more suitable for outdoor cropping than others. Larger fruits take longer to grow and ripen, so if youâll be planting them outdoors, with a shorter growing season, itâs best to choose a variety with smaller fruits. Youâll also find several dwarf or compact varieties, ideal for containers on a sunny patio or balcony, or even a kitchen windowsill.When choosing, look in particular for varietieswith an RHS Award of Garden Merit (AGM), which should grow and crop reliably â see our list of AGM fruit and vegand ourRecommended Varietiesbelow.Youâll also find sweet peppers growing in the veg areas at theRHS gardensover the summer months, so do visit to compare varieties and pick up growing tips.
What and where to buy
Sweet pepper seeds are widely available in garden centres and from online seed suppliers. Many also sell young plants in spring and early summer. These are ideal if you donât have a suitably warm, bright place to raise good plants, or just want a few plants. Grafted plants may also be available â these are more vigorous and should crop more reliably in cooler growing conditions. They can be ordered from online suppliers for delivery from mid-spring.
Recommended Varieties
'Bianca'
Mid-season-variety with large fruits ripening from cream to yellow. Plant grows to 60cm tall.
The RHS Award of Garden Merit (AGM) helps gardeners choose the best plants for their garden.
Wild bees and other pollinators are in decline. The Plants for Pollinators initiative helps gardeners easily identify plants that encourage them back into the garden
'Corno di Toro Rosso'
Large, tapering fruits up to 25cm long. Sweet flavour, crisp texture and thin skin.
The RHS Award of Garden Merit (AGM) helps gardeners choose the best plants for their garden.
Wild bees and other pollinators are in decline. The Plants for Pollinators initiative helps gardeners easily identify plants that encourage them back into the garden
'Jolly Giallo'
Square-shaped, fleshy fruits, 12cm long, with mild, sweet flavour.
The RHS Award of Garden Merit (AGM) helps gardeners choose the best plants for their garden.
Wild bees and other pollinators are in decline. The Plants for Pollinators initiative helps gardeners easily identify plants that encourage them back into the garden
Showing 3 out of 6 varieties
3
Sowing
Section 3 of 8
For step-by-step sowing instructions, see our guides below.
4
Planting
Section 4 of 8
Give sweet pepper plants plenty of light and warmth â they grow best above 15°C (59°F)
Sweet peppers will grow and crop best in a greenhouse, polytunnel, conservatory orcoldframe. In very warm, sheltered locations, you can plant them outside too, once overnight temperatures are reliably at least 12°C (54°F). However, they are likely to produce fewer fruits outdoors, and the shorter growing season means the fruits may struggle to ripen before temperatures start to drop in late summer.Before planting outside, carefullyharden offyour plants for a couple of weeks, to acclimatise them to outdoor conditions. Give them your warmest, sunniest spot, ideally on a sunny patio or beside a south-facing wall, with temperatures of 15°C (59°F) or more. Plant them in their new location at the same level they were previously growing in their pot, and add canes to support taller varieties.
Planting in containers
Plant your young peppers into their final container in late April if growing in a heated greenhouse, mid-May in an unheated greenhouse, or late May/June to grow outside. Choose a container at least 30cm (1ft) wide, and usepeat-freemulti-purpose compost, or plant two or three in a standard growing bag. Add canes to keep the plants stable and upright. See our guides below for more tips.
Planting inthe ground
Choose a spot with well-drained, fertile, moisture-retentive soil that is ideally slightlyacidic. To achieve this, dig in moderate amounts of well-rotted manure, at a rate of 5.4kg (10lb) per square metre/yard, but avoid using fresh manure or large quantities, as this can lead to lush, leafy growth at the expense of fruit. Next,warm the soilwith cloches for a couple of weeks before planting. Space sweet pepper plants 38â45cm (15â18in) apart, depending on the variety. Compact varieties can be spaced 30cm (1ft) apart. Then cover young plants withclochesto provide wind protection, preferably until the end of June.
5
Plant Care
Section 5 of 8
Temperature and humidity
Sweet peppers can cope with a minimum night temperature of 12°C (54°F), but will grow better if kept above 15°C (59°F). But they don't like to be too hot â temperatures over 30°C (86°F) can reduce fruiting, so keep the greenhouse well ventilated and put up shading in summer.
Peppers also likehumidity, so add moisture to the air in warm weather byâdamping downâ the greenhouse regularly â poura full watering can over the floor, leaving it to evaporate duringthe heat of the day.
Watering
Water regularly to keep the potting compost or soil evenly moist, ensuring plants neither dry out nor get waterlogged. They may shed their flower buds if theyrun short of water.Also apply mulch to damp soil to help retain moisture around the roots.Plants in containers may need watering daily in summer, as the compost will dry out quickly.
Feeding
To encourage fruiting, feed sweet pepper plants once a week with a high-potassium liquid fertiliser, once flowering starts.
6
Pruning and Training
Section 6 of 8
Pinch out the tip of the main stem when plants reach about 30cm (1ft) tall, to encourage side-shoots to form, which should lead to more fruit. You can also pinch out the tips of the resulting side-shoots if you want more but smaller fruits.
Support each plant with a sturdy bamboo cane, tying in the main stem as it grows. If plants produce a heavy crop of large peppers, more support may be needed as the stems can be quite brittle and snap easily. Insert bamboo canes around the plant and attach the fruit-laden side-shoots using soft twine.
7
Harvesting
Section 7 of 8
Harvest sweet peppers regularly, to encourage further fruiting
Related RHS Guides
8
Problems
Section 8 of 8
Aphids are attracted to sweet pepper plants, so check shoot tips and under leaves regularly to prevent colonies getting established. Several other sap-sucking insects can be problematic too, especially in a greenhouse and in dry conditions. See below for details. Young pepper plants also need protection from slugs and snails.
