There’s never been a better time to plant your own onion sets. Easy-to-grow and full of flavour, home-grown onions are often bigger than those in the shops and they store exceptionally well too. They’re also great value for money. Depending on the time of year, you’ll need to choose from autumn-planting or spring-planting onion sets. Here’s a quick summary of each to help you decide…
Autumn-planting onion sets
Thompson & Morgan’s autumn planting onion sets are hardy varieties that have been bred for overwintering in UK conditions. Best planted out in September and October while the soil is still warm, they’ll be ready to harvest from June, two months earlier than spring-planted sets.
If you have limited space and want to keep your veg patch as productive as possible, autumn-planting onions can be harvested just as you need to make room for other crops. Choose a combination of varieties depending on what you like to cook with. ‘Centurion‘ (yellow), ‘Shakespeare‘ (brown), ‘Electric‘ (red) and ‘Autumn Champion’ (pickling) are all reliable choices.
Spring-planting onion sets
Thompson & Morgan’s spring planting onion sets have been specially heat-treated for 20 weeks to help prevent summer bolting and extend their growth period, leading to bigger yields and bigger bulbs at the end of the season. Planted out in March and April, they’re usually ready to harvest from August.
Onions harvested in late summer can be prepared for storage and used right through the winter. If small, expensive supermarket onions won’t cut it for you this season, try a large variety like ‘Stuttgarter Giant’ (yellow), or ‘Setton’ (brown), both selected for their uniform bulb shape, full flavour and long storage qualities. ‘Red Baron’ adds a bright flash of colour to salads and stir fries, and if you’re after variety, a mixed onion collection offers excellent value for money.
For more information about growing onions from seeds and sets, take a look at our onions, garlic and shallots hub page where you’ll find articles, videos and lots of top tips.
Kris Collins works as Thompson & Morgan’s quality control manager, making sure customers new and old are kept up to date on the latest plant developments and company news via a wide range of media sources. He trained in London’s Royal Parks and has spent more than a decade writing for UK gardening publications before joining the team at Thompson & Morgan.