Planting Onions & Shallots for Winter
If you’ve spent any time in garden centres recently, you’ve probably noticed that among the stacks and stacks of spring bulbs are a few packs of onions and shallots. Not quite so appealingly packaged, but nonetheless, a timely reminder that now is the time to plant onion and shallot sets for overwintering.
Why plant onions in the autumn?
There are several very good reasons for planting onions in the autumn:
1) They will have a head start in the spring over any onion sets that you plant then. This also means that your winter-sown onions will be ready for harvesting sooner, saving valuable spring and summer space in your vegetable patch.
2) There is nothing else using the space in your vegetable patch over the winter, so you don’t really have anything very much to lose by putting in a few onions and shallots.
3) It gives you something positive to do at a time when an awful lot that’s going on in the garden is about pulling things out and clearing for winter, so it’s a bit of a feel-good activity.
How to choose and plant winter onions
Some varieties of onion seem to be considered particularly suitable for winter planting. Fortunately, you don’t need to know much about it, since it’s really only these varieties that are available now! So whatever you can buy in garden centres will be suitable. Once bought, plant as soon as possible, and don’t keep them hanging about. Oh, and don’t be tempted to replant any of your summer onions as an alternative to buying sets, as this could spread disease.
Planting both onions and shallots is very easy. Follow the spacing guidelines on the packet, but as a rough guide, they should be about 15cm apart, with rows slightly further apart for easier weed clearance.
Use a rake or trowel to make a narrow furrow about 2-3cm deep. Place the onions in the furrow, with their roots downwards, at the required distance, and gently rake the top soil back over the bulbs so that only the tips are still showing. At this time of year, you probably don’t even need to water them in, although it may be helpful if your soil is particularly dry.
Why would you not plant winter onions?
On sandy and light topsoil, there’s really no reason not to plant winter onions. Your yield could even be better than on spring plantings. But on clay or heavy soils, you may find that your onions rot over winter, especially in a wet or very frosty year. You’ll just have to try it and see if you think it’s worthwhile in your soil. After all, that’s what gardening is all about!