In the UK pepper plants are normally treated as annuals, that is they are sown in the spring, harvested over the summer and autumn, then allowed to die in the winter. However, all peppers – that is sweet peppers and chilli peppers – are perennials, capable of living for several years.
Peppers come from the tropics where there is no winter period. In Britain, though, it is a different story, and the cold temperatures and short days of British winters is a serious impediment to the survival of these heat-loving plants. Thus, if a pepper plant is to survive these difficult months it will need special care.
Firstly, the plants must be kept in a frost-free place. This means they cannot be left in an unheated greenhouse or polytunnel. It only takes one cold night for the plants to be killed off. The best place to overwinter a chilli plant is in the house, an environment warm enough for humans will be fine for a chilli plant.
As important as temperature is, it is not the only issue for chilli plants in the winter. Capsicum species also need high light levels to grow and be healthy, something that is sorely lacking in British winters. Not only are the days short in winter, but also the sun shines less, and even when it does its rays are not as powerful as they are in the summer. No matter how warm the temperature, the low light levels of winter will stress the plants.
Pepper plants often respond to stress by dropping their leaves. So the stress from low light levels in the winter is likely to make pepper plants behave like deciduous bushes, i.e. drop their leaves and go dormant. When this happens watering must be reduced; over watering results in wet compost that will damage the roots.
Although the leaves fall off the chilli fruit often doesn’t. So if there are any fruit left on the plant they should be picked off.
If the plant has got overlarge, this is a good time to prune it back into a more suitable shape and size. But do leave plenty of stem on it, and certainly do not cut it right back to the base.
As the plants are not growing they do not need to be kept in a prime sunny position, and provided the area is frost free can be left in a corner to wait the winter out.
In the spring
In March, as the increasing day length starts to feel significant, return the plants to a sunny position and this should stimulate them to burst into activity and produce new leaves. As the leaves appear increase the watering as necessary.
March is also a good time to repot the plants, giving the plants new, fresh compost. The roots are likely to be pot bound, so it is a good idea to rip the roots out a bit, which will stimulate new growth.
© Joy Michaud