Onions and shallots

Are you seeking information about old and new varieties of onions? – Or are wondering what is the best time to plant them? Or how to harvest and store the bulbs?

One of my friends chose onions as the major subject for her degree in botany. It just shows how much there is to learn about onions. She passed on one or two good tips, and some ‘everlasting’ onions. Read on for more about this plant and other members of the Alliaceae family.

Choosing varieties

Main crop onion (Allium cepa)

‘Ailsa Craig’ is an old, white-fleshed variety. It produces large bulbs that keep well. ‘Hygro’ is high yielding and ‘Red Baron’ a red onion, but for a variety that can give you huge show bench onions, go for ‘Unwins Exhibition’. And for an onion to grow from sets, rather than seed, consider ‘Setton’.

Spring onion

‘White Lisbon’ is a quick growing salad variety. ‘Guardsman’ is recommended for the home gardener, as the onions can be left to grow longer before they form bulbs, and ‘Onion Feast’ is new for 2002.

Pickling onion - for a silver-skinned variety, seek out the new ‘Pompeii’.

Shallots (Allium esculentum)

Choose ‘Red Sun’, which has good keeping qualities, or ‘Ambition’ – a new variety for 2002.

Welsh onion (Allium fistulosum)

Grow some Welsh onions and you need never be without an onion. This non-bulbous perennial, the so-called everlasting onion, keeps on increasing. So long as the whole clump isn’t gathered, the few remaining onions will continue to produce more stems. Each clump looks something like a bunch of spring onions about 12 ins in height.

Planting

A well-drained sunny site is ideal for onions. Prepare the soil thoroughly by digging in compost during autumn. In spring, produce a fine soil by raking the ground during dry weather. Gardeners in cold areas like to get ahead by sowing main crop varieties of onions in January, under glass, and planted out in April; but onions may also be sown outdoors in March in some areas. Sow in rows 10 in apart, thinning to 6 in apart.

Sets are small, immature onion bulbs that are planted as an alternative to seeds. They are usually set about 4ins apart from mid March until mid-April.

Shallots are full-sized onions that increase in number when you plant them. Gardeners harvest about six to eight onions for every one that is planted - easier than growing onions from seed. They are usually planted about 6 in apart in February to mid-March.

Welsh onions are usually started as newly purchased young plants. Place them in the soil, 9 in apart, in March and April. Thinning is unnecessary.

Pickling onions are suitable for growing in a sandy soil. There is no need to thin them out.

Harvesting

Salad onions are sown at intervals in spring and summer, and pulled as soon as they have grown large enough to add to salads.

A sign that other types of onion are ready to harvest is when the leaves turn yellow in summer and early autumn. Let the foliage dry back, then lift with a fork and allow the onions to complete their ripening on top of the soil – or under cover in rainy weather. They can take a month or longer to finish ripening.

Shallots and sets are harvested between July and September, depending on the whereabouts of the location. Welsh onions may be harvested from the beginning of June.

Storing

Hang bulbous onions up to dry, if possible – or store undamaged ones in nets, or on trays. Plaiting them into long French onion strings is a picturesque way to keep them through winter. A dry, cool place is best for long term storage.

Ornamental onions

The giant ball-headed varieties of Allium giganteum make splendid additions to sunny gardens, as do some of the alpine species. (Species of Allium that are grown for their flowers deserve an article to themselves).

Over-crowded clumps of ornamental onions can be divided and replanted in autumn or spring. Did you remember to plant the free ‘Lovely Lady’ sweet pea seeds, sent with orders for allium varieties Globemaster and White Giant? - part of an Unwins offer to customers. Sweet peas can be sown directly into the garden in March and April. The onions should come into flower in May or June.

Chives (A. schoenoprasum) - ‘Pink Perfection’ has attractive flowers and the foliage is edible. There is still time to sow seeds of edible and ornamental onions in March.