Last Updated on February 19, 2024 by Jason Nguyen
Chillies are hot right now and it’s not just their flavor. They are one of the top-selling plants for edible gardens.
It seems we just can’t get enough chilli and, for many chilli fanciers, the hotter, the better!
If you’re not a fan of super-hot chillies, grow one of the milder flavored varieties or stick to capsicum.
The heat of a chilli comes from a chemical known as capsaicin. The sweet chilli or bell pepper, better known in Australia as capsicum, is just a large chilli that lacks capsaicin, so it’s sweet, not hot.
Chilli Facts
Common name: Chilli, pepper
Botanical name: Capsicum annuum
Family: Solanaceae
Aspect & soil: Sun; well-drained soil
Best climate: Cool to tropical
Habit: Biennial vegetable
Propagation: Seed, seedling
Difficulty: Easy
VARIETIES
The chilli’s varietal names often indicate its Central and South American origins and give a hint to its pungency.
The ‘Trinidad Scorpion’ from the Caribbean is as dangerous as it sounds, though names aren’t always a good guide to heat – the benign-sounding ‘Scotch Bonnet’ (named for its resemblance to a tam o’shanter — a traditional Scottish bonnet) is a very fiery customer.
Chilli berries vary from small and round (like ‘Scotch Bonnet’) to long and skinny like the tabasco or jalapeño, but color, shape and size are no indication of heat.
The best guide to the heat of a particular variety is its number of Scoville heat units (SHU), which reflects levels of capsaicin.
The SHU should be taken as a guide only as growing conditions and fruit maturity also affect how much capsaicin is in the chilli and how hot it tastes.
As a guide, a capsicum has no heat units, a jalapeño chilli is rated 2500–8000 SHU while the habanero, a hot chilli, is 100,000–350,000.
Scotch bonnet is rated at 100,000–400,000, making it one of the hottest of the chillies normally found in gardens, but it’s eclipsed by the ‘Trinidad Scorpion Butch T’ variety, which has been recorded at an eye-watering 1,463,700 on the Scofield scale.
ORNAMENTAL AND EDIBLE
Growing a selection of chillies in the garden or in a container provides a range of spicy flavors to use in the kitchen.
This mixed planting can also create an ornamental feature as chillies come with lots of variation in appearance as well as flavor.
Chillies are usually thought of as red but there are varieties that are green, purple and orange and some with mottled colors, so the plants look attractive as well as being edible.
Chilli plants that are sold as ornamental may have hot-tasting fruit. However, check the plant label carefully before eating them as a chilli lookalike, Solanum capsicastrum, often sold as winter cherry or ornamental capsicum, has toxic fruit. Admire but don’t eat.
The fruit of Capsicum annuum is, however, edible. So-called ornamental varieties of chilli include ‘Little Elf’.
Whether ornamental or edible, always keep chilli plants well away from children.
Children can be attracted to the bright colors of chillies in the garden and will suffer severely if they pick or eat one.
For safety, keep chilli plants out of reach by planting them in the centre of a raised garden bed or in an elevated pot, or by keeping them well fenced.
GROWING TIPS
Chillies are in the Solanaceae family, along with tomatoes and potatoes.
They grow best through the warmer months of the year (spring to autumn) but, unlike tomatoes, many chillies continue to grow through winter to resume flowering and fruiting the following spring.
They are frost sensitive, especially when small. To keep a chilli growing into a second year in an area that experiences cold winters, grow it in a pot and move it into a frost-free spot as winter looms.
A sunny, sheltered patio, a glasshouse or against a warm wall are ideal positions to overwinter a chilli plant.
Plants grow to around 40–60cm high. They can be grown in a garden bed or in a container; select a pot or trough that’s at least 25–30cm wide for good growth.
Chillies are sold as seed, seedlings or small plants. Sow seeds from August to December in cool to mild climates, July to March in subtropics and year-round in the tropics.
Seedlings and small potted plants are best planted into the garden or containers from spring to summer in cool to temperate zones but can be grown year-round in the subtropics and tropics.
Dig a little lime into very acidic soils before planting to reduce problems with calcium deficiency such as blossom end rot, which can occur as fruit matures.
As chillies have a strong branch structure, they don’t need staking, although a stake gives extra support in an exposed, windy situation – or if the branches are brittle and heavily laden with fruit.
When the weather warms, chillies begin to flower then form fruit. Keep plants well watered as they grow — water daily when it’s hot and dry — and protect small plants from slugs and snails.
Aphids and whitefly may attack chillies. Control these pests with sticky yellow traps or an organic insecticide registered for edible plants such as eco-neem, Natrasoap or a pyrethrum product, but don’t spray when bees are about.
Larger chilli fruit may also be attacked by fruit fly. Use a fruit-fly lure and bait to reduce damage, especially as fruit ripens.
Feed plants once they’ve begun to bloom. Apply a complete fertilizer every six weeks or liquid-feed potted plants fortnightly. Lightly prune plants to encourage new growth after harvesting.
HARVESTING
Use secateurs or scissors to harvest ripe fruit to avoid breaking the branches and always wash your hands well after harvesting chillies to avoid burning sensitive skin.
The color of a ripe chilli will vary depending on its variety but may be red, orange, purple or mottled.
Harvest chillies as they are needed. Preserve bountiful crops by drying, freezing or plaiting the fruit into an attractive kitchen decoration.
WARNING
Chillies aren’t only hot to eat. Just handling the fruit can lead to burning. Capsaicin, which gives the chilli its hot kick, is found in the skin, the membrane inside the fruit, the juice and the seeds, so always wash your hands carefully after harvesting or preparing chillies.
Avoid touching your eyes or mouth until after you’ve washed your hands.
