GROW GUIDE - CHILLIES & SWEET PEPPERS
There are a great many misconceptions with chilli plants, to start this guide off I will try to cover a few of these, for those who want to jump ahead, do feel free.
Whilst there are a large number of chilli experts, many people instead know chillies as a hot red blob people put in curries. That is pretty much the furthest thing from the truth. Chillies come in a wide spectrum of colour and taste, from green to purple to black or brown and from smoky to fruity, citrus or hot burning agony.
Chilli plants are quite possible to grow outdoors in most parts of the UK, however the hotter the chilli, generally the more heat required to produce them and the longer it takes to germinate them. The best results will be given if you have a sheltered sunny position but we will also cover how to grow them indoors if needed.
The most important thing to bear in mind is start early.
Before starting germination, you should know what sort of chilli you have, as there is a wide variance of light and heat requirements for germination then knowing what you have will help you get a strong plant. The species also gives you a guide as to what can be overwintered and how easily they germinate.
Capsicum annuum: Despite the name, the annual chill is actually perennial if looked after well, They are derived from north America and therefore they benefit from a hot but slightly dry environment. Whilst this doesn't mean desiccated, they will cope with poor watering better than some other chillies and they develop stronger taste in such situations.
Capsicum baccatum: This species is best known for Aji chillies, often described as semi-domesticated, they produce very few seeds and have a low germination rate (60-80%), however this is more than offset with the high vigour and superb taste these plants provide. Of particular note is Lemon Drop and Dedo De Mocha, the first one being lemon scented and flavoured, with the second having a low heat which reveals the deep smoky complex taste characteristic of the Aji group.
Capsicum chinense: There has been some debate about chinense and if it is actually the same species as annum, they share certain characteristics however when crossing between the two species, there is a loss of fertility compared to interspecies crossing. The epithet chinense is like annuum, completely wrong as all chillies derive from the new world. They germinate readily and contain some of the hottest chilli cultivars such as habanero and Trinidad scorpions.
Capsicum pubescens: Pubescens means hairy, making this the hairy chilli although the other common name is the tree chilli. This species is very rare and distinctly different to other cultivars. The most important difference, and where it gets the tree chilli name, is that it reaches maturity quickly and can live for over 15 years and tolerate the cold much better than other cultivars, making them superb for overwintering. There are reports that the plants can reach four meters or more by the time they reach old age and they can be extremely prolific. The other differences are they have slightly hairy leaves, purple flowers and black seeds!
Growing chillies from seed is the traditional, most common way to start a plant out, as the seeds are small, they should not be planted too deeply, ideally just a surface covering to preserve moisture. Although if you want to do it in bulk, it is quite possible to sow into seed trays or half trays (here we do about 40 seeds to a half tray to fit in our propagators) you will generally get better results sowing into plugs or cell inserts as you can leave them in until they have formed their second leaf sets. If you do it in half trays, you may get better results by re-potting them earlier so you don't damage the roots of other seedlings.
Initially chillies only require heat and moisture to germinate, this this varies between cultivars always try to look up the species before germination, If you are growing numerous species then just try to keep the heat constant, such as in a propagator. An ideal seed mix would be 40% JI Seed, 40% multi-purpose and 20% pearlite with a covering of fine vermiculite, however for most non-specialist chilli seeds, multi-purpose compost should be perfectly fine. Try to keep them slightly moist throughout germination (and I don't mean drowned!).
With the first sign of germination then move the plants to somewhere slightly cooler and well lit. The best time for sowing seed is mid-late January if you have a heated propagator.
After the chilli plants have germinated then you should see two leaves emerge, these are the cotyledons or seed leaves. The pair after this are the first "true" leaves and when they are about 1cm long, this is the stage you will want to re-pot them if you planted them singly. Handle them gently and by the leaves, supporting them from the roots with a label. When pricking out seeds you should always lift from below the root zone with a pencil or label. Although the seedlings are tougher than you would think, its still not a good idea to recklessly damage them. For the first pot use a liner (10cm) and after it has developed a root system big enough to reach the drainage holes in the bottom of the pot, re-pot it into a 3L.
After a few weeks from re-potting you can start feeding it, there is a lot of conflicting information on what to give chilli plants, however it boils down to not too much nitrogen, tomato food or vitax q4 is ideal. Keep re-potting it until its reached the size you want and as the weather warms up then you can move it outside if you want, into a sheltered place overnight, just be sure to acclimatise it as time goes on.
At some point (time determined by the cultivar), if you haven't killed it by following my instructions, you should start to see flowers appearing. If the plant is outside then you don't need to do much as bees will readily pollinate them, the only thing to watch for is that the plant doesn't dry out to the point of blossom drop (don't confuse this with pollinated flowers dropping as the chilli will push the flowers off), A little heat or dryness will stress the plant slightly and as a result increase the heat of the chilli fruits.
If the chilli is grown under cover or you are using the seed saving method below, shake the plant slightly and this will help release the pollen and increase fruit set.
Notably unlike tomatoes, you should not try to encourage overly strong root growth, even the earliest chilli plants are slower than tomatoes and they can struggle to ripen properly or have reduced yields if they spend too much time developing roots.
You can harvest chillies at almost any time after the fruit has reached its full size. Over time the fruit will ripen and change colours, this will also change the taste characteristic which is in most cases mild at first before developing heat later. Again the colour and ideal time to pick depends on the cultivar you are growing. The best way to harvest is with a sharp craft knife or secateurs and cut above the fruit with a clean cut. You can then use the fruit in a number of ways, there are instructions on drying and seed saving below.
Congratulations! But this is not the end, there is so much more you can do with this plant, even after taking fruit!