The onion sets you buy are immature bulbs which have been specially grown for planting. There are several advantages in using sets rather than seed. They are quick maturing, succeed in northern areas where seed-sown crops may disappoint and they are not attacked by onion fly or mildew. Less skill and less soil fertility are required, but against these advantages must be set the extra cost and the extra risk of running to seed (‘bolting’). Modern varieties are much less prone to bolting – another safeguard is to buy sets which are no larger than ¾ in (2cm) across. The shallots you buy are already full-sized – when planted in early spring they quickly start to grow and eventually produce a cluster of 8 to 12 similar-sized bulbs in summer.

Set facts
‘Heat-treated’ onions sets: flower embryo has been killed to prevent bolting.
‘Virus-free’ shallots: stock is free from virus yellows.
Expected sprouting time: 11-14 days
Approximate number per lb (onion sets): 80
Approximate number per lb (shallots): 30
Expected yield from a 10ft row: 7lb (3.5kg)
Life expectancy of stored seed: 3 years.
Approximate time between sowing and lifting: 20 weeks (onion sets); 18 weeks (shallots)
Ease of cultivation: Easy

Soil facts
· All onions require good soil and free drainage, but sets need neither the fine texture nor the high organic content demanded by seed-sown onions.
· Dig in early winter and incorporate compost if available. Lime if necessary. Firm the surface before planting and rake in a general fertilizer such as Growmore.

Planting
· Push gently into soft earth that is in slight dips 4in (10cm) apart, with dip rows 9in (23cm) apart. The tip should be just showing. Firm around the sets.
· If planting is delayed, open package and spread out sets in a cool well-lit place to prevent premature sprouting.
· Plant onion sets 4in (10cm) apart in mid March-mid April. Shallots require wider (6in (15cm) apart) and earlier (mid February-mid March) planting.

Calendar
Planting time: As above
Lifting time: August; can extend from July to September.

Looking after the crop
· Protect from birds with black thread or netting if they are a nuisance in your area.
· Keep weed-free by hoeing and hand pulling. Push back any sets which have been lifted by frost or birds. Once the sets are established and shoots have appeared then treat as for seed-sown onions.

Harvesting
· Shallots: In July the leaves will turn yellow. Lift the bulb clusters and separate them, allowing each shallot to dry thoroughly. Remove dirt and brittle stems, and store in net bags or nylon tights in a cool, dry place. They will keep for about 8 months.
· Onions: See Onion from seed.

Varieties
Onion varieties
Stuttgarter Giant: This is the variety you are most likely to be offered. The bulbs are flattened, not round, and the flavour is mild. It has good keeping qualities and is slow to bolt.
Sturon: Many experts will tell you that this variety is a better choice than the old favourites. The straw-coloured bulbs are round and extremely large. Bolt resistance is excellent.
Ailsa Craig: An old favourite – round, large and straw-coloured with white, mild-flavoured flesh.
Rijnsburger: Large, pale yellow and round. There are other large, round onions but this one (also listed as Giant Fen Globe) has outstanding keeping qualities. Stays fresh in store till May, according to the catalogues.

Shallot varieties
These small bulbs are milder in flavour than onions and are harvested in July or August. Use for cooking, garnishing or pickling – keep a few in a cool, well-lit place for planting next spring.
Dutch Yellow: One of the basic varieties – depending on the catalogue you will be offered Giant Yellow, Long Keeping Yellow, etc. Like Dutch Red, a popular choice for kitchen use.
Hative De Niort: The usual choice by exhibitors – the bulbs are perfectly shaped with deep brown skins.

Troubles
See Onion from Seed