Chilli Seed Propagation and Plant Care
Learn to grow your chilli seeds and plants from the experts. We were featured on the BBC Gardeners World program during their 2006 chilli seed trial. To purchase chilli seeds go the the chilli seeds page.
In the UK, chilli seeds need to be sown early in the year, and grown on in a greenhouse or poly-tunnel though they can be grown outside in a sunny spot during the height of summer. Germination can be very variable between varieties and can take as much as five weeks, though the varieties we sell on our seed page should all germinate within 10-14 days, some sooner. To help you get going, we have listed some of the tricks and guidelines we use to give our chillies the best start possible and for growing them on in pots.
We recommend that you use soil-based seed and potting-on composts - chillies really appreciate good drainage. We recommend J Arthur Bowers with John Innes loam based seed compost for germination.
Warmth and Surface Watering
Germination speed and percentage is greatly improved by applying warmth to the seed compost. We use thermostatically-controlled heated propagators, but placing the seed pots/trays in a warm environment or on a simple heated tray will also work well. With the seed compost at 27-32°C (80-90°F), you should see good results. Seeds will still germinate down to 21°C (70°F) but germination will be slower and more erratic. If the temperature drifts towards 38°C (100°F) germination will be quick but there will be a lower success rate
Try to use surface watering with a spray botthe rather than watering from the base, surface watering has less effect on the temperature of the compost. Don't over water, and certainly don't make them swim. Watering with a sprayer causes less impact.
We mainly sow seeds during February and March, but you can leave it later. There is a great variance in the number of days taken for a particular variety to reach maturity. Some can produce ripe fruit in 60 days from sowing and others take as long as 120 days.
Remember that varieties such as Habaneros take 100 or more days (3 1/2 months) from potting on to reach maturity. So these need to be started in good time or the fruit will never ripen.
We tend to sow seeds about 5mm deep and in small pots, with a number of seeds of the same variety in each pot. Keeping each variety in its own pot is a good idea because germination time varies greatly. As soon as the majority of the seeds in a pot have emerged and are showing two well formed leaves, and certainly before they become leggy, they should be transferred into 3 inch pots. Hold the seedlings by the leaves, and not the stems. Note that some seedlings may need a little gentle help getting free of the seed pod. If you have the propagator space you can sow directly into 3 inch pots.
At this stage they should be moved to a site where they will get plenty of sunlight; ideally to a heated greenhouse or warm conservatory. Continue to keep them warm, moist and well ventilated. They can stay in a 3 inch pot until they are 3 to 6 inches high.
When the plants have about 5 pairs of leaves they should be potted on into larger pots. We grow most of our plants in the ground and this is a possibility if you have a polytunnel or open soil in your greenhouse. Otherwise pot on into 9 to 12 inch pots depending on the variety. You can use smaller pots for compact ornamental varieties. As the summer sun intensifies, you may need to provide some shade, for example, lining your greenhouse or painting with greenhouse paint.
Try to keep the plants below 36°C, don't feed them a lot of nitrogen and don't let them dry out. That should help prevent blossom-drop and pod-drop. Larger varieties may need support with a cane. Ornamental varieties can be moved to a bright position in the house or to a patio once they are well established. If your flowers are dropping off there could be a number of causes. If they are outside it is probably cold windy weather. If they are indoors it could be lack of himidity, in which case give them a mist spray. Lack of feed will also
Different varieties are picked at different stages of their development. Fruits that start yellow or green generally ripen to red, though green chillies will sometimes ripen to orange or yellow, it all depends on the variety. Usually, and regardless of the colour, once they have filled out and become firm crisp and glossy they can be picked. Experiment by picking one to see if it has all it's heat and flavour. The sooner you pick the more the plant will produce so even if you don't need them at the time you should pick them and keep them in the freezer until you do.
Most chilli plants can be treated as perennial house plants, but will need some pruning in the winter. Some varieties are better suited than others, smaller hot varieties like Serrano and Twilight, and Prairie Fire do better than the bigger fleshy plants such as Poblano and Anaheim.