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Discover Onions

Here’s the chance for you to discover some of the basic facts about Onions as well as some essential growing tips. Use these to decide whether you want to grow the vegetable, whether you are able to and what you need to do or look out for in order to grow a bountiful crop!

Onion Fact Sheet
OnionSpring Onion
Other names: Allium cepa
Popular varieties: Centurion (light skin), Hyred (red skin), Setton AGM (dark skin)
Interesting fact: Used by Roman gladiators to rub into their bodies to harden muscles
Nutritional value: Full of vitamins A & C and minerals
When to grow: Mid spring or autumn
Grown from: Seed in and planted out when strong enough or baby onions that are planted directly into the ground
Likes: Sunny & sheltered site; dry conditions; good drainage; free of weeds when growing and covered with fine net and fleece to avoid pests
Dislikes: Freshly manured ground; growing on same ground every year (risk of pests/diseases);frost and weeds
Harvest time: Mid-to late summer when leaves are yellow and tops are bending over
Watch out for: Diseased bulbs (fluffy white growths) when harvesting
Cooking tips: For seasoning sauces, soups, curries, stews and salads
Essential Growing Tips for Onions

There are two main types of onions - spring onions and large globe onions.

> Yellow skinned globe onions grow bigger than red skinned varieties. Salad onions are milder tasting.
> You can grow onions from seed or from sets (small baby bulbs). Sets are more expensive, but quicker to grow.
> Seeds should be sown in greenhouses from January. When large enough to handle, separate them into rows in trays or in pots. Seed sown onions can be planted out in the garden in early spring.
> Before planting them out, make sure they have got used to the outside temperatures. Leave the pots outside for longer and longer times until they can be left outside all day and night. Then they will be ready for planting in the vegetable patch. Using a coldframe or plant house helps this hardening off process too.
> Sets can be planted 10cm (4”) apart straight into the soil in early spring. Plant each set so that the top just shows above the soil. Break off any flower heads which appear.
> When the bulbs have swollen in late summer, pull back the earth from the bulbs. Let them lie on the earth exposed to the sun for a few days.
> Spring onions can be sown from seed straight into the earth every three weeks from spring to midsummer. Plant a small amount of seed each time. This will avoid having too many onions ready for harvesting and being unable to eat them all.
> Onion Fly is the main pest. The flies lay their eggs in the bulbs. When the eggs hatch, the maggots eat the bulbs. Try growing onions next to carrots or parsley to mask the smell. This can confuse the onion flies. Insect-mesh protection netting with its fine mesh size will also help to keep Onion Fly at bay.

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