Growing chillies from seed

Introduction

Growing chillies from seed can be very rewarding. This may seem like a lot to take in, but please don’t let it put you off – it is intended as a helpful guide to give you a better growing experience. Of course chillies can be germinated and grown in a variety of ways and you don’t have to do it exactly this way, but this is what has worked best for us over the years of trial and error!

Germination – pre-soaking

First you need to decide whether or not you are going to pre-soak your seeds. Pre-soaking can lead to quicker germination and a higher germination rate, but is not necessary. When we are planting hundreds of seeds at a time, pre-soaking slows things down, making them more difficult to handle. However, if you are only planting a few seeds, it is well worth the extra effort. Your seeds can be soaked in several different solutions. Some people swear by chamomile tea as it is meant to have antibacterial properties. Others use plain distilled water – but never straight from the tap, as the chemicals and chlorine can affect germination. You can also use a dilute Hydrogen Peroxide mix – around 2% Hydrogen Peroxide is ideal. This is good as it can kill off certain diseases that may have been carried through the seed. They should be soaked overnight, but not for more than 24 hours. If the temperature can be controlled at about 25C, this will also speed up the germination process.

Sowing

Then you need to choose a medium to plant your seed in. You can plant the chilli seeds in seedling mix, coco peat, jiffy pellets or rock wool cubes. Personally we didn’t have much success with seed raising mix, as it seems to dry out too easily, we find peat plugs are easy to use and resist drying out. This is a picture of the polystyrene trays that we use, each tray holds 240 plugs:

When you plant the seed, you only need to cover it with a thin layer, generally a depth of around 1 – 1.5 times the size of the seed. If you are using rock wool or jiffy pots you will need to pre -soak them in distilled or rain water (Rockwool needs to be PH adjusted). Then just pull off a small amount of that medium and place it on top of the hole which you just sowed the seed into. 

Seeds are best started indoors on a heat pad around June/July. Most of the cheaper heat pads do not contain a thermostat, so you may need to buy a thermostat to plug your heat mat into. Chillies need above 20 degrees Celsius to germinate but prefer temperatures around 23 – 30 degrees Celsius. Night time temperatures can’t fall to under 15 degrees Celsius. The superhot chillies require constant (day and night) temperatures of 28 – 30 degrees Celsius for optimum germination success.  

Heat pads without a thermostat generally raise the temperature 10 degrees above ambient room temperature. If you also keep them in a mini greenhouse this will keep the moisture, humidity and heat in. It is good to have a vent open or lift the lid once a day to prevent stale air once they have sprouted. With humidity it can be common for your growing medium to start growing green algae. I haven’t found this to affect germination but can look a bit unsightly.

Seeds are meant to be moist but not soaking and the medium you have chosen should never be allowed to dry out or become water logged. If they are too wet they can rot and break off at the stem (damping off). Misting with a spray bottle works quite well and keeping the lid on your mini greenhouse will help.

You should also try to use pure water like rain water or distilled as the chlorine in tap water can prevent germination. Although we use mains water, we actually water from a tank, so that hopefully most of the chlorine has broken down before it reaches our seedlings. We also add Chilli Focus to the tank water to make feeding our chillies even easier!

Early growth

Most seeds should sprout by 2 weeks but some of the c. chinense varieties can take up to 6 weeks. Please be patient and don’t throw them out too soon. You will also need to feed them with liquid nutrients that you can get from us (Chilli Focus) or another type from a hydroponic shop if it is not in soil. Chilli seeds do not need light to germinate but once they do they will need light to grow.

The first two leaves you will see are called cotyledons and are not the ‘true’ leaves. When they have grown their first few sets of true leaves it is time to pot them up. Start with a small pot and work your way up.

Once they have sprouted they will need light. If you are raising them under fluorescent grow lights start with having the light about 10cm away from the top of the seedling and then raise it as the seedling grows. Seedlings need 18 hours of light a day, so it is best to put it on a timer. At night time the plant starts using all the nutrients and energy that it has gathered during the day, so it is best to give them a rest time. If you are moving them outside don’t use direct sunlight or else they will burn. If there isn’t sufficient light then your seedlings will become leggy, pale and weak. We actually put our seedlings into the greenhouse around August – September as soon as we have transplanted them into their first small pots.

You will also need to open the vents gradually to allow fresh air in.  You can have your setup in a little cupboard or tent with the light hanging inside so the light rays don’t spread out too far. It would also be a good idea to put a little circulating fan and another one pulling out the old air and excess heat.

Hydroponics

Sun & Watering

Most chillies and especially the superhot chillies do best in morning sun only. If you are getting temperatures above 30 degrees and your plants are in the full sun all day it is recommended to put up some shade cloth. This will prevent burning on the fruit and leaves as well as preventing flower drop. We grow our chillies in shade tunnels using 50% shade cloth.

Ornamental chilli plants like to be kept in areas which receive a large amount of light for optimum colours and also like to have a liquid feed (fertiliser such as Chilli Focus, Miracle Grow or a seaweed solution) every 1 – 2 weeks.

Chillies don’t necessarily need watering every day. It will depend on whether they are in pots or the ground and what the weather is like. If the top couple of centimetres of soil is dry but underneath is damp then they are fine. They don’t like to have “wet feet” so don’t sit them in a tray of water.

Chilli plants can also very hardy. If you haven’t given them enough water and the leaves are wilting, just give them a good soaking. Ususally within an hour or two they will perk back up. You don’t want to do this too often but once the plant has fruit on it and you water stress them then it also makes the chillies hotter. If you do this when they just have flowers then they will drop them. If you need to water in the middle of the day try not to water the leaves – the droplets of water can act as magnifying glasses and burn the leaves.

Now that you have your seedlings growing, you can look forward to a season of growing your own fresh chillies! However, there are still a lot of things that can go wrong – check out our next article for some more advice on successfully growing your chilli plants.