Capsicums
Bell peppers, Cayenne and Jalapeño – Capsicum frutescens; Peppers, both mild and hot – Capsicum annuum; Hot chillies, such as naga and habaner – Capsicum chinense
These have been grown and harvested for as long as 10,000 years, in the warmer parts of both Americas – Peru and Bolivia especially.
Introduction
Often called capsicums, these are all in the nightshade or Solanaceae family. They have been grown and harvested for as long as 10,000 years, in the warmer parts of both Americas – Peru and Bolivia especially.
The cool summers at Homeacres do not allow their full expression of quality and sweetness. Afternoon temperatures through summer average 21–22 °C/low 70’s °F here, therefore I struggle to grow capsicums outdoors but do reasonably well with plants under cover. My aim in this lesson is to give you an idea of possibilities.
There is some confusion in categorisation between what we call chillies and sweet peppers. The Latin names above show that it’s not a clear distinction. In terms of growing any of these plants, the most important thing is that they are closely related. As a result their needs are similar, to achieve successful harvests.
Harvest period
- Days from seed to first harvest: 100 for unripe peppers and chillies, 125 for ripe fruits.
- Best climate is a warm to hot summer, with days of 24–35 °C/75–95 °F, and first frost not before mid-autumn.
Why grow them
In a warm climate, peppers can be highly productive for several months after midsummer. You have the choice to pick them green and unripe, or sweeter with colour, and there are many colours to choose from.
Chillies are both easy to grow and give a lot of harvest, even from small plants growing in containers. There is a huge choice of varieties.
Pattern of growth
Although mostly grown as annuals because of dying in any frost, these plants are perennial.
They take a fair time to flower and then fruit, and even longer for peppers to ripen. The size of plants varies between different varieties, and peppers can grow tall if grown as cordons.
Suitable for containers/shade?
Chilli plants especially are suited to container growing, but they need as much sun as possible. In the first year, they do not grow into large plants, so a 20 cm/8 in pot is sufficient to produce 20 or more chillies.
Pepper plants are more hungry than chilli plants, so use a 30 cm/12 in pot and the best multipurpose compost you can find. You will probably need to feed pepper plants as well, from the middle of summer, using any proprietary feed.
Perennialise chilli plants in containers
You can prune any chilli plant, to about 50% of its size, in mid to late autumn. Bring the pruned plant to any room in the house for two to three months over winter – the pots can even be out of natural light. Do not water at this point.
Once past the winter solstice, you should see some new leaves appearing and plants need to be in the lightest place you have. Give as little water as you dare, then, once there are no more frosts, you can move the pot outside. At this point, tap out the rootball and place all the contents into a larger pot for a second summer of growth.
- I grew the chilli plant below through four summers – it worked better than I had expected.
The most difficult time is late winter, when new leaves are often full of aphids. However, as soon as the plants are outside and/or under cover in full light, aphids are no longer a problem, having been eaten by predators.
- A further option is to bring plants inside before frost, without any pruning. This is not guaranteed to succeed but I did manage it once with a Habanero chilli – see the photo under ‘Water’ below.
Varieties
There are many fine pepper varieties, with different offerings every year in catalogues. Best select those that appeal to you, according to their description. Use my photos for ideas too.
- If your climate has a summer cooler than the ideal, which is the case for much of the UK, it’s important to remember that the photos of highly coloured peppers are achievable only in warm conditions.
Bell peppers are almost rectangular in shape, with a thick skin, and the harvest can be heavy. Often they are available as hybrids, such as Bell Boy and Bendigo.
Hungarian Hot Wax grows pointed peppers, unusual for being of variable heat, some mild and some spicy.
Roter Augsburger grows well in cooler conditions but, if it’s windy, growth is not worthwhile – see the photo in ‘Planting’ below. The fruits are medium-sized, slightly pointy and tasty when ripe red.
For chillies there are fun shapes to try as well as a range of colours and heat units. Bishops Hat is a beautiful fruit, Lemon Drop is easy to grow and of medium heat, Alphonso Loco makes a large plant with really hot, black-seeded chillies.
Sow and propagate
- Seeds germinate in seven to ten days.
Sowing time
Seeds and seedlings need warmth, and the plants require a long season of growth. Therefore you must have options for indoor sowing, as early as the middle of February and up to mid-March/late winter to early spring.
It is possible to sow for another month after that, always with good warmth and light.
Sowing method
It can be two weeks or more between sowing and full development of the cotyledons. This makes it worthwhile to sow in a small tray, so that less of your warm space is needed for those first two to three weeks. Then prick out the seedlings into module cells, after two to three weeks in the seed tray.
Pot on?
This is necessary in order to keep plants growing to a respectable size, until it is warm enough to plant them out. The slow growth means that a 7 cm/3 in pot is probably large enough. Then, if not ready to transplant after three weeks, you can pot this into a 10 cm/4 in pot.
Transplant, interplant
Transplant size and time
Plants can be 20–30 cm/8–12 inches tall, and they may even have a first flower or two. Plant out at your normal time for warmth-loving plants, after the last frost of spring.
Transplant method
Use a trowel to make a hole slightly larger than the rootball and 5 cm/2 in deeper, and push in firmly.
For container growing, a 30 cm/12 in pot should be large enough for one pepper plant. Chillies can grow in a smaller pot.
Spacing
If your summer is hot, the pepper plants can grow large and need up to 60 cm/24 in each way. For cooler summers, 45 cm/18 in works fine.
Chilli plants can be as close as 35 cm/14 in apart.
Support
Even for commercial growers, this can be a vexing question. It is possible to grow pepper plants as cordons, with two leading stems per plant.
However, this involves a lot of time, removing sideshoots very regularly. Pepper plants grow more sideshoots than tomatoes, partly because there is a shorter distance between the nodes of each main leaf.
I find it simplest to put a stout bamboo in the soil, close to the main stem. Let the plant grow as it wishes and loop a string around later, once you notice branches drooping with the weight of developing peppers. Occasionally a branch may snap off because they are fragile at the joint with the main stem.
- Find the way that works best for you and according to how much time you have.
- There is some support needed for most pepper plants.
- Chillies, on the other hand, rarely need support because the fruits are so much lighter and plants are more compact.
Transplant size and time
Plants can be 20–30 cm/8–12 inches tall, and they may even have a first flower or two. Plant out at your normal time for warmth-loving plants, after the last frost of spring.
Transplant method
Use a trowel to make a hole slightly larger than the rootball and 5 cm/2 in deeper, and push in firmly.
For container growing, a 30 cm/12 in pot should be large enough for one pepper plant. Chillies can grow in a smaller pot.
Spacing
If your summer is hot, the pepper plants can grow large and need up to 60 cm/24 in each way. For cooler summers, 45 cm/18 in works fine.
Chilli plants can be as close as 35 cm/14 in apart.
Support
Even for commercial growers, this can be a vexing question. It is possible to grow pepper plants as cordons, with two leading stems per plant.
However, this involves a lot of time, removing sideshoots very regularly. Pepper plants grow more sideshoots than tomatoes, partly because there is a shorter distance between the nodes of each main leaf.
I find it simplest to put a stout bamboo in the soil, close to the main stem. Let the plant grow as it wishes and loop a string around later, once you notice branches drooping with the weight of developing peppers. Occasionally a branch may snap off because they are fragile at the joint with the main stem.
- Find the way that works best for you and according to how much time you have.
- There is some support needed for most pepper plants.
- Chillies, on the other hand, rarely need support because the fruits are so much lighter and plants are more compact.
Water
Chilli plants need little water because of their slow growth and small size. Pepper plants in hot conditions need less water than, say, aubergines – perhaps twice a week and with a decent amount each time.
Use a trowel to check soil moisture – remember that it’s fine when only the surface is dry. If it’s also dry lower down, give plenty of water.
- Container-grown pepper plants need water every day once they are growing strongly.
- Chilli plants in containers outside may need water as little as once every five days in damp weather.
- Water chilli and pepper plants less, once most of the fruits are showing signs of colour.
Extra mulch to retain moisture?
This is rarely needed, except in arid conditions.
Prune and thin
Fruit thinning is not needed because these plants sort it themselves. The main time you need to reduce growth is six to eight weeks before first frost, when it’s good to pinch off all new growth which usually has flower buds. They would not have time to grow into worthwhile fruits.
Harvest times and methods
How to judge readiness
You have more choices here than for most harvests. What we call unripe peppers and chillies are edible. It’s a question of how you like to eat them.
- With peppers, the main difference is extra sweetness once they have changed colour.
- The original colour is not always green; on some varieties, it may be beige or purple.
How to pick
Use a sharp knife to cut through the stalk of a pepper that you want to pick. It is possible to lift peppers sharply upwards to detach them. However, this can sometimes break the plant stem.
Chilli stalks detach more easily and can be picked simply by pulling upwards to detach them.
When to pick and how often
This mainly depends on how ripe you like them to be. For fully ripe/coloured peppers in a temperate climate, it can mean waiting until early autumn before taking any harvest at all. As a result, we often eat green peppers and pick just a few, so that there are a few to ripen in time.
Chillies are good to pick on demand, with a big harvest by mid-autumn when they are mostly coloured and leaves are often yellowing.
Storing
Peppers keep for three or four weeks in cool conditions, and if picked green but fully developed they may start to show some colour after a week or two. They will be less sweet than if ripened on the plant.
Chillies store well, even when picked green, for at least a month and more in winter. You can also store them in a jar with some oil, which then becomes very hot.
Saving seed
The flowers of all these plants will cross-pollinate. Even peppers and chillies can cross so, if you want to save seed, best grow just one variety or keep it where insects won’t find other varieties nearby.
For chillies at least, it’s more realistic to keep a pruned plant over winter, as I describe above in the section on container growing. You can also do this with pepper plants but you need more space and a larger pot because they are bigger.
Potential problems
Pests
Aphids
In spring, these are often on new and tender growth.
I advise not to worry, just spray or jet a little water to keep them in check and, once conditions become warmer and lighter, plants grow more strongly with less interest for aphids. Also, predator insects arrive by early summer.
Slugs
These eat weak seedlings and peppers close to ground level. They should not be a problem if you transplant once it’s warm and keep developing peppers above ground level.
Weedkiller in compost
I hope that most people will not be troubled by this but it’s present if your plants show deformities of growth, with particular shrivelling at the growing points or tips, sometimes together with paler leaves. There are probably weedkillers in the compost you have used.
There was, for example, a totally new incidence of this in Melbourne, Australia, in December 2020. The compost from a large recycling facility caused damage in hundreds of gardens. When the company analysed the compost, they were horrified to find traces of dicamba, 2,4-D, MCPA, triclopyr and picloram.
It turns out that much of this came from grass clippings brought to the facility for composting, from lawns sprayed with weedkiller that contains these horrible ingredients, including clopyralid. There is no way that the company could check every delivery of material to compost.
- These products need to be banned.
- Pyralids in particular can remain active in compost for many years and are dissipated only by soil microbes, not compost microbes.
If this should happen to you, check out this link on Twitter, where you can make a comment to alert other people about the source of your compost.
And finally
Clear
Use a trowel or sharp knife to cut around the main roots, just below the stem. Some twisting will help to break any remaining roots and leave most of them in the ground.
If you have grown plants in containers and don’t want to overwinter them, pull them out and drop the compost on any bed in the garden, or use it for winter salad plants.
Follow with
Plants under cover will finish by mid-autumn, which gives time to transplant salads and leafy vegetables for winter harvests. You need to have sown these in early autumn, so that plants are already four weeks old.
