Bulbing onions can be used all year round, either fresh from the garden or storage. Yellow, red and white-skinned varieties are available, with more or less pronounced flavour and keeping abilities. Varieties sown in spring (or earlier under glass) or grown from sets (small bulbs) are ready to harvest from late summer onwards and keep until the following spring. Seed or set varieties started in late summer or early autumn stay in the ground over winter and mature in early summer after stored onions are used up – these varieties only keep until the new year.
Onions grow best in a sunny site in rich but light soil, that is relatively free-draining. They'll tolerate a range of soils, as long as it's firm.
Allium cepa 'Sturon' is a full-flavoured white onion, bearing straw-coloured bulbs that mature in August. The Royal Horticultural Society have given it their prestigious Award of Garden Merit (AGM). For best results, grow Allium cepa 'Sturon' in full sun in well-drained soil.