There are thousands of chilli varieties to grow, in a huge range of colours, shapes, sizes and levels of heat, from mild to extremely hot. Many have unique flavours, with some offering a hint of lemon and others having a more fruity taste.
A chilli’s heat is measured on the Scoville scale, a test created in 1912, in which the more water needed to dilute a chilli solution before a human taster can no longer detect the chilli determines the number of Scovilles. Today, testing is done by machines. A score of around 3,000 Scovilles is deemed hot, with record-breaking chillies such as ‘Carolina Reaper’ topping two million mark.
Many chilli varieties are available to buy in supermarkets but you will have a much greater range to choose from if you grow chillies yourself. They’re very easy to grow from seed, and grow best in containers, which means they are perfect for a sunny patio or balcony. You can also buy ready-grown chilli plants at the garden centre in spring.
All chillies are bred from just five species:
- Capsicum annuum – the most common chilli species, from which sweet and paprika peppers originate.
- Capsicum baccatum – includes the aji family of chillies, popular in Peruvian dishes.
- Capsicum chinense – a hot variety of chilli, from which we have habanero and scotch bonnet chillies.
- Capsicum fruitescens – where tabasco Thai-style chillies come from.
- Capsicum pubescens – these are hot chillies with distinctive black seeds.
Several online nurseries specialise in chilli seed, offering a range of interesting and unusual varieties you can use in different dishes, from Mexican salsas to Thai curries.
How to grow chillies
Sow chilli seed indoors as early as January if you have a heated propagator, or from March if you don’t. Transplant seedlings into individual 7.5cm pots when the first true leaves appear. Eventually, transplant them into 30cm pots of peat-free, multi-purpose compost. Wait until all risk of frost has passed before moving them to their final growing positions outside, in a sunny spot. For the hottest chillies, grow in a greenhouse. Chillies are tender plants, so will not survive the winter. It’s best to sow seeds for fresh plants each year.
More on growing chillies:
- 12 chillies to grow
- How to store chillies
- Hot chillies to grow
Chillies: jump links
- How to sow chilli seed
- Caring for chillies
- Six steps to hotter chillies
- Harvesting chillies
- Storing chillies
- Problem solving
- Chilli varieties to grow
How to sow chilli seed
Chillies need a warm, sunny spot for the best results and the hottest chillies. Ideally, grow them in a greenhouse or raise them in pots on a south-facing patio or windowsill. Chillies need a long season to grow, so it’s best to sow seed as early as January in moist, peat-free multi-purpose compost, and keep in a heated propagator under a growing light, to prevent seedlings going leggy (sow seed in March if you don’t have a heated propagator). Pot on into individual pots when the first true leaves appear. Keep potting on if growing in pots or plant out into the greenhouse when night temperatures exceed 10ºC – ensure the soil or compost is free-draining. Feed weekly with a high potash fertiliser once plants have started flowering, and harvest chillies as and when they appear.
Chilli varieties to try
Best chillies for a window sill
‘Thai Hot’ or ‘Hot Thai’ – tiny, very hot fruits on a compact plant
- Buy chilli ‘Hot Thai’ seeds from Suttons
‘Pretty Purple’ – small, round fruits that start off purple and ripen to yellow and orange, then red
- Buy chilli ‘Pretty Purple’ seeds from the South Devon Chilli Farm
‘Malawi Birdseye’ – a medium hot variety with small fruits that mature from green to red
- Buy chilli ‘Malawi Birdseye’ seeds from Nicky’s Nursery
Best chillies for a patio or balcony
Chilli ‘Apache’ – these tough dwarf plants cope well outdoors. The pretty green fruits mature to red and are medium hot
- Buy chilli ‘Apache’ seeds from Dobies
Chilli ‘Firecracker’ – small, attractive fruits
- Buy chilli ‘Firecracker’ seeds from the South Devon Chilli Farm
Chilli ‘Chilly Chilli’ – attractive, ornamental fruits in a range of colours with hardly any heat
- Buy ‘Chilly Chilli’ seeds from the South Devon Chilli Farm
Mild chillies
Chilli ‘Ancho Poblano’ – great for stuffing and baking
- Buy chilli ‘Ancho Poblano’ seeds from the South Devon Chilli Farm
Chilli ‘Cascabel’ – round, almost black fruits that are often used dried
- Buy chilli ‘Cascabel’ seeds from Nicky’s Nursery
Medium hot chillies
Chilli ‘Hungarian Hot Wax’ – long fruits that are good for stir fries. They are harvested yellow to keep the plant fruiting, but eventually ripen to orange
- Buy chilli ‘Hungarian Hot Wax’ seeds from Thompson & Morgan
Chilli ‘Joe’s Long Cayenne’ – the finger-like chillies, up to 25cm long, can be eaten green or red
- Buy chilli ‘Joe’s Long Cayenne’ seeds from the South Devon Chilli Farm
Very hot chillies
Chilli ‘Ring of Fire’ or ‘Ring O Fire’ – long, pointed fruits that ripen from green to red
- Buy chilli ‘Ring of Fire’ seeds from Dobies
Chilli ‘Bhut Jolokia’ – extremely hot, wrinkly fruits – formerly considered to be the hottest chilli in the world
- Buy chilli ‘Bhut Jolokia’ seeds from Suttons
‘Trinidad Scorpion’ – extremely hot, wrinkly fruits
- Buy chilli ‘Trinidad Scorpion’ seeds from the South Devon Chilli Farm
‘Carolina Reaper’ – reputed to be one of hottest chillies available, at two million Scoville units.
- Buy chilli ‘Carolina Reaper’ seeds from Dobies
