How to Grow Peppers
Sweet peppers - or bell peppers - are a star ingredient in salads and stir fries, with chillies turning up the heat in all their many varieties. Here’s our step by step guide to growing peppers and chillies.
Most common Pepper plant questions
Can I grow Peppers outside?
Peppers should be ideally grown in cover such as in a greenhouse or polytunnel.
They need consistently warm temperatures to be fully productive - a warm conservatory or windowsill is also fine.
When can I plant Peppers?
Peppers are best planted from May to June.
If you are planting outside you may want to cover them in a horticultural fleece to give them extra warmth and protection
How to plant Peppers
If you are planting Peppers in pots then plant them individually in 6L pots. If you are planting peppers in the ground then plant them at least 40cm apart.
Fill your pot with compost and then dig a small hole just big enough for the plant’s roots to fit in. Place the plant’s roots in the hole, backfill the gaps with soil and then gently firm the plant in with the tips of your fingers. Give the plants a watering to help the soil settle around the roots.
We recommend that for Peppers you plant them in pots as this makes them easier to move around into sunnier and more sheltered locations if they need extra heat and sunshine. Just ensure the pots have proper drainage holes so the roots do not become waterlogged and rot.
What kind of soil do Peppers need?
Pepper plants like fertile-well draining soil.
Three parts quality compost with one part topsoil is a great mix.
How much sun do Peppers need?
Peppers need the maximum amount of sun available –at least 6-8 hours of direct sunlight every day.
How much water do Peppers need?
There is a difference between how you water Sweet Peppers and how you water Chilli Peppers.
For Sweet Pepper plants, you need to be water them regularly to keep the soil moist, but you must also ensure it does not become waterlogged. During hot summer days, this may require watering every day.
For Chilli Peppers, you can make the peppers hotter by letting the soil dry out. There is a fine balance you must strike between letting the soil dry out but also giving the plant enough water so that it does not die. You should allow the soil to completely dry out over the course of several days and then give the plant a heavy watering.
If you are planting Peppers in pots it is a good idea to place the pot on a saucer. This means when you water it, it will drain out to the saucer where it can be sucked back up by the plant as and when it needs it.
How to feed Pepper Plants
As soon as the plants begin to produce flowers, start feeding them every week.
Use a high-potash fertiliser such as liquid tomato feed.
Potash, or potassium, is one of the three main elements in fertilisers along with nitrogen and phosphorus. Potash in particular supports growth of flowers and fruit and so this feed is often increased as the fruits or flowers are beginning to form.
Do Pepper plants need support?
Pepper plants will often need some support as they grow.
This can easily be done by planting a small stick (a bamboo stick works great) about 3cm from the base of the plant. Tie in the main stem to the stake with some garden string.
Loop a couple of times around the stake and then tie to the stem to avoid rubbing and damage to the plant
How to care for Pepper plants
You will need to pinch off the growing tip, which is the highest growth stem growing up vertically, once the plant has reached around 8 inches. This will encourage more lateral growth which will allow the plant to support for fruit growth.
How to harvest your Peppers and Chillies
To harvest the Peppers simply cut them away from the plant using a sharp pair of sterilised pruning scissors.
Cut them away from the plant at the stalk.
Sweet Pepper varieties take around 60-90 days to grow (depending on conditions such as heat and moisture).
Chillies can take 60 days to ripen but most take 90-120 days.
The Peppers will be ready to harvest when they have taken on their final colour.
Common Pepper plant problems
The most common problems that affect Peppers in the UK are Blossom End Rot, Whitefly, Aphids, and Red Spider Mites. Read below for specific information on each issue.
What is blossom end rot?
Blossom End Rot appears as black, rotten blotches that develop from the bottom side of the fruit.
It is caused by a lack of calcium in the plant which means the plant’s cells degrade, leading to extended rotting.
Quality soil, such as potting compost, will always have enough calcium in it. The reason why the plant isn’t getting enough calcium is because the soil has become too dry for extended periods of time, meaning that the plant cannot extract the calcium from it.
To prevent Blossom End Rot you must ensure the plant’s soil is kept consistently moist. Touch the soil, and if it feels dry to the touch a fingernail down, then the plant needs a watering.
Whiteflies look like small white moths and are most commonly found on the underside of leaves.
If left unchecked they will feed on the leaves and turn them yellow.
Your best, natural defence against whitefly is to simply spray your plant down with some water, aiming it at the whiteflies to try and wash them off. Make sure you check the whole plant and get as much off as possible. If the problem persists you can buy a special bug spray that specifically targets these pests and is safe to spray on your peppers.
Aphids are small green bugs that cluster on the stems, particularly at the joints, and also the underside of leaves.
They cause leaves and fruit to discolour and become misshapen. Aphids also leave behind a sticky residue known as honeydew which can then promote the growth of a fungus known as sooty mould.
Like Whiteflies, ladybirds and hoverflies enjoy eating aphids so planting Marigolds nearby will help control the pest. Also, the same chemical sprays that work for Whitefly tends to also work against aphids. You can also use soapy water to try and wash the aphids off of the plant.
Red Spider Mites
Red Spider Mites are tiny (about 1mm) red arachnids that can become a common pest in greenhouses.
If left unchecked they can cover entire leaves in webs while sucking the sap from them causing leaf drop and sometimes even the entire plant to die.
To prevent Red Spider Mites from infesting your Pepper plant you should keep the leaves moist. Do this by misting the leaves daily.
You can also use biological control against Red Spider Mites, such as predator mites include Phytoseiulus persimilis. These can be readily bought and are a good, natural way to control pests.
If the infestation is serious you can also use pesticides. It is better to use organic pesticides with short persistence–this will reduce damage to other organisms.