One of the most versatile vegetable crops, onions are a staple in a huge variety of dishes, from hot curries to soups, salads and tarts. But do you know your onions? Not every onion is the same and some types lend themselves better to certain dishes than others.
Bulbing onions, Allium cepa, can be used all year round, either fresh from the garden or stored. Yellow, red and white-skinned varieties are available, with differing flavours and storing potential. They can be grown from seed or sets (small, immature bulbs) in autumn or spring, and are ready to harvest from early to late summer (those sown/planted in autumn spend winter in the ground and are ready to harvest sooner than those sown/planted in spring). Onions grow best in a sunny site in rich but light soil, that's relatively free-draining. They'll tolerate a range of soils, as long as they're firm.
Find out more about yellow, red and white onions, as well as shallots and Egyptian walking onion, below.
Not every onion is the same and some types lend themselves better to certain dishes than others.
Yellow onion 'Setton'
Yellow onions are the most commonly used type of onion. They have a strong flavour, a yellow skin and crisp white flesh. They have many uses in the kitchen, and are especially useful as a base for stews, curries and sauces. Sow seed or plant sets in spring. 'Setton' is an improved version of traditional cultivar 'Sturon'. It has a more uniform shape, bears higher yields and has better storage potential than 'Sturon'. 'Setton' also has a good, strong flavour.
Red onion 'Hyred'
Red onions are sweeter than yellow or white onions, and are an excellent choice for salads. They can be finely chopped and used in guacomole, and may also be pickled. Onion ‘Hyred’ is an F1 hybrid onion which forms a rounder bulb and more of an intense red colouring than some other red onion varieties. It's less resistant to bolting, which is more common in red onion varieties. Plant sets in spring.
White onion 'Snowball'
White onions have much more delicate flavour than yellow onions, and are commonly used for thickening sauces and in salads and Mexican dishes, where less intense 'oniony' flavour is required. With a thinner skin, they don't store as well as yellow onions. 'Snowball' has good, round bulbs and a mild flavour. Plant sets in spring or autumn.
Unlike onions, which grow individually as bulbs with a single stem, shallots grow in clusters, bulking up from one clove, a little like garlic. They're easy to grow and store well - much better than onions. Most varieties are smaller than onions, are more delicate in structure, and contain less water (which means they need to be cooked more gently). Their flavour is much milder and sweeter than that of onions, so if a recipe specifies shallots, using onions instead won't give you the same results. Plant sets in spring.
Egyptian walking onions
The Egyptian walking onion, Allium proliferum, propagates itself from bulbils – effectively 'walking' around your garden. In spring its narrow green leaves may be harvested and eaten as chives. As the bulbs develop they can be harvested as spring onions, or left in the ground to harvest later as shallot-sized onions. Any plants left in the ground will grow small bulbils at the tip of the leaves. These become heavier, causing the plant stems to bend until the bulbils touch the ground, where they develop roots and grow into separate new plants. Plant in spring.