The overwintering of chilli plants, in temperate areas anyway, is probably the most variable and uncertain part of chilli growing. The most detailed advice is, at best, to be taken with a pinch of salt as there are so many more variables to think about when you compare overwintering with, say, germination. How warm is the autumn? how cold is the winter? where are they kept? what variety? How long are the daylight hours?
So rather than dispensing general advice, which I, and many others have done before, I will illustrate some practical examples of what has happened to some of my experimental plants this winter. For a little bit about what happened to some of my plants back in the autumn you can link to the blog entry ‘When Will My Chilli Plants Die?’.
Where I live near the coast of south Devon in the UK, we have had what is, so far, undoubtedly the mildest winter ever, so I still have a few plants that would not normally survive. This is as good as it gets, and things haven’t been great, so this illustrates the general advice that you should bring any plants that you want to keep into the house where they stand a very good chance of survival. The hardier of my plants were busy fruiting in my greenhouse until Christmas. Up until that point we had only two mornings when there was frost on the ground, and even then the greenhouse temperature only dropped to 3c. Often temperatures were 15 or 16°C and not far of that at night times. It was really really dull and wet though, so I wasn’t hopeful for some plants that I left outside.
Through January temperatures were still warm, and it is only in the last couple of weeks that we have had consistently lower temperatures, but still the greenhouse hasn’t dropped to lower than 1°C.
Despite the warm early winter I am still not surprised to see that most of the plants I tried to overwinter in the greenhouse or outside are looking doomed. There are a few which will survive, but 4 months of short days and just a couple of months of cool temperatures have still mounted up so that only the real hardy ones will live on.
I had little doubt that this rocoto would survive, they are pretty hardy and this one wasn’t pruned back till January, and at the end of February it is still looking nice and green. It is in a smallish pot in the greenhouse.
This rocoto, above, wasn’t as lucky. It was very much an experiment, it grew well outside in a vegetable patch protected by climbing beans all around, but the wet soil and a battering by the wind means it is unlikely to shoot out again this year.
This 3rd rocoto was overwintered outside the greenhouse in a large pot, it is looking pretty good, the stems all nice and green, the soil drains easily and I hope it will shoot out in the spring. I will move it into a greenhouse to give it a kick start.
Rocotos are generally one of the safest bets when it comes to overwintering. The others that do well are the baccatums, ajis, and some of these have done OK in the greenhouse.
The botton aji limon is looking green and healthy, but the one above is dead at the main stem, so I am not hopeful for this one, I think the main stem will rot down and cause the plant to die.
Finally, this is one of my old faithful piri piri plants. This is its second winter, it will stand colder than anything thrown at it so far and I am confident it will do well again this year. The stems are still green up to about 1m high and I have only pruned the straggly small stems to keep it in shape. It is in a big pot, which keeps the roots insulated against sudden drops in temperature, and it is under glass.
I started off hanging on to other plants, either to see which was the first to go, or to test out some new ones. I have never overwintered Carolina reaper before, so I tried that. In the house is OK, but a couple in the greenhouse died back quite quickly. Likewise various annuums they didn’t do well in the greenhouse either and are already in the bin. I wouldn’t normally try keeping these anyway, things like jalapenos don’t perform as well in their second year as newly seeded ones, but as October and November were so mild I hung onto a few.
This last one was an annuum that I did secretly hope would survive, as it would have been great to see it shoot out early. It is a pimento de Padron, and was nearly 2m high in a greenhouse bed, but I’m not sure if it will grow again, watch this space.