Sow onion seeds this week – it's the perfect antidote to itchy fingers desperate to get gardening. Traditionally you sow onions on Boxing Day – but you can do it any time until the end of February. The earlier the better, though, as you'll need to give them a long growing season to produce the plumpest bulbs.
Exhibition growers swear by sowing onions in the coldest months of the year – and not just because it gets them out of doing the Christmas washing up. You get a better choice of varieties compared to growing from sets – just look at the great range of onion seeds you'll find on offer at your favourite garden centre. And onions sown from seed don't bolt as quickly, store better, and can form much bigger bulbs – which is why they're so popular with growers who show.
If you'd like to try growing giant onions, choose your variety carefully: 'Ailsa Craig', 'Bedfordshire Champion' and 'Lancastrian' are all whoppers. Sow into modules of good-quality seed compost, and pot on to a larger pot as soon as their roots appear at the drainage hole. Plant outside in April and keep watered and fed to produce mammoth bulbs by autumn, just ready for the shows.