How to Grow Chillies from Seed
How to Grow Chillies from Seed
Growing chillies from seed is fairly easy as long as you have a warm, light nursery for them. The key to success is to start early enough.
Whilst chilli plants can grow like rockets later in the season, they are notoriously slow to start. The earlier you can plant, the longer the cropping season is going to be.
This is essential if you want your chillies to ripen by the end of the season. I've grown hundreds of thousands of plugs and plants from seed and I've condensed everything you need to know into the Step by Step planting guide below. Follow the instructions and you can't go far wrong.
It's worth remembering that chillies are tropical, so growing them in northern climates requires getting them enough heat and light. There are, of course, ways to cheat nature and give your chilli plants a great head start, effectively extending your growing and cropping season.
Heated propagators are an obvious addition, speeding up propagation and growth and there are a number of low-tech grow lights that can easily double the length of the day for your young seedlings.
Starting off your seeds
The easiest and most effective method of planting is to use pre-formed Coir Jiffy pellets. Soak them until they have swollen to size and put two seeds into each one, just below the surface. Remove the weaker seedling later. If you are planting into pots, fill with a free draining compost mix.
Peat is fairly disastrous for chillies as it is too cold and wet. A good mix is a 50/50 blend of coir and compost. Fill one pot per seed type to about 2cm below the rim, firm down the compost and soak thoroughly.
Place the seeds with a good space between them so that you do not harm the roots when you come to potting on and cover them with a fine layer of compost. Use separate pots or trays for each variety and don’t forget to label them.
How to propagate chillies
For best results, place in a heated propagator or a seed tray with clear lid in a warm place. Around 25-30ºC is ideal and this will significantly increase germination and speed it up.
In a heated environment, you should start to see some action in 7-10 days. Germination can be erratic, especially with chinense varieties and you may see seedlings emerging for several weeks.
Caring for chilli seedlings
As the seedlings start to appear, introduce some ventilation to your propagator or seed tray, being careful to maintain warmth at night as plants are very vulnerable to the cold at this stage.
Keep the compost moist but not wet. Overwatering is the biggest cause of chilli plant problems and it can easily encourage damping off at this stage.
The seed contains enough energy for the seedling to produce its first set of true leaves so there is strictly speaking no need to feed at this stage. A 1/4 strength seaweed feed can offer a helping hand though.
Growing on from plug size
Four to six weeks after germination, seedlings should have produced their first two sets of true leaves and can carefully be potted on, avoiding too much root disturbance.
If you have planted into Coir Pellets, just pop the whole thing into the new pot. Plant into 9cm pots, using a free-draining compost, again a 50/50 mix of coir and compost is ideal.
Chilli plants do well in warm, sunny places so a heated greenhouse, conservatory or sunny windowsill is ideal. Keep a close eye on your young plants, making sure they do not dry out. Feed them weekly with a seaweed or dedicated pepper feed.
Potting on from plant size
After another 4-6 weeks, plants will be outgrowing their pots and ready to move on. You can either pot into an intermediary 1 litre pot or they are ready for their final positions. Final pots should be 7 to 20 litres, depending on how much space you have. Again, using a free draining compost/coir mix, carefully pot on.
By this stage an unheated greenhouse should suffice. This is obviously dependent on the weather. Chillies don’t like the cold and shouldn’t be left unprotected if the temperature is going to go down below 10ºC. In the summer months, hardier annuum chillies can be placed outside in a sheltered spot or on a warm patio. Acclimatize them slowly, bringing them in at night for the first week or whenever the temperature threatens to drop. Chinense varieties prefer the shelter of a greenhouse.
Where necessary, use a cane to support the plants as they grow. Carry on feeding chillies with a dedicated chilli feed or seaweed extract at the suggested rate. A weekly foliar spray of Epsom Salts (Magnesium Sulphate) will encourgage leafy growth. Keep the compost moist, plants well spaced and make sure there is some ventilation.Keep a careful check of any pests in the greenhouse, as they are better dealt with before an infestation starts.
Flowering & fruiting
Once your plants have produced their main side shoots, pluck out the growing tips to encourage more side stems. Once flowering starts, switch to a higher potassium feed, such a s half-strength tomato feed.
Chillies are insect-pollinated but that failing, they will self-pollinate, so a gentle shake of flowers will help ensure that they set.
If you want a bumper crop of pods, feed at the suggested rate. However heat-stressed plants will produce a smaller crop of superhot pods. Feed at half the suggested rate and let your plants almost dry out, watering them a little as they start to wilt.
If watching plants grow from seed to bear flowers and fruit does not get you hooked on chillies, the heat and flavour of your own fresh pods is sure to. Fresh off the plant, their flavour is fresher, fruiter and more intense.
Experiments with Growing Media
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We conducted two separate experiments with growing media. The first was to ascertain the best mix of compost and coir for loose planting and the second to ascertain how that fared against Jiffy Coir Pellets. Four trays were planted with an annum variety (Jalapeño) and a chinense variety (Habanero).
Coir is well known to provide a loose, friable bed and to absorb excess moisture, releasing it when necessary. Compost, on the other hand, provides many of the nutrients needed by young seedlings. The trays of seedlings shown are around four weeks past germination during which period they were watered carefully but no extra feed added. The nutrient additive that came with the coir, added to the tray at the top was clearly far too strong for the seedlings and they never made it. The results speak for themselves, a 50/50 mix of compost and coir provides the best of both worlds. Start your seeds off with World of Chillies Grow Kit.
In a second stage of the experiment, a tray of 50/50 coir and compost was planted at the same time as a tray of 30mm Jiffy Coir Pellets and a tray of 50mm Jiffy Coir Pellets. The tray on the left looks like it is doing much better than the centre one, however there are 100 pellets in the tray on the left vs 40 in the central one. Both trays of Jiffy Pellet seedlings have far outgrown the seedlings planted in the compost/coir mix. Potting on plugs and plants.
Chilli Varieties in Brief
Chinense chillies
Chinense chillies; belonging to this species are the hottest pods on the planet. All of the extreme chillies Carolina Reaper, Trinidad Scorpions, Seven Pots, Morugas, Bhuts and Nagas belong in this group as well as a whole range of pretty hot chillies such as Habaneros and Scotch Bonnets.
These are the most difficult plants to grow. If you are growing in the UK, you will need a greenhouse and a bit of time and knowhow to care for these plants. If you haven't planted chinense varieties by the end of February, either get hold of plugs or plants or choose a different variety.
Annuum chillies
Annuum chillies; generally, annuum chillies are much easier to grow than the chinense. Although all chillies would prefer a greenhouse, some varieties of annuum will bear fruit outside if you have a sheltered, sunny spot. Cayennes, Jalapeños, Pimiento de Padron all crop well outdoors.
Annuum varieties will flower from mid summer and you can expect chillies from July onwards. There are some hot varieties but none that compare to the extreme heat of the chinense pods. However, if you are a beginner, don't have a greenhouse or just want an easy life, annums are for you.
Other species
Other species; Rocotos are alone in the pubescen species, with their hairy leaves and round, black-seeded pods. These are difficult to get going, and very susceptible to stunted growth if not cared for properly. However, if you can get them to a good size, they will flower and fruit prolifically.
A number of chillies from the baccatum species are becoming increasingly popular, such as Aji Amarillo, Aji Lemondrop and Brazilian Starfish. You will need a greenhouse to protect these plants from the British weather but given that, they are easy to grow and crop prolifically from quite early in the season.
Growing tips from World of Chillies
Chilli Problems
Chilli Blogs
Chilli Nutrients
Potting On Chillies
Chilli Pests
Chilli Diseases
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