Vegetable Gardening

The Garden Farm - the way to self-reliance

Find us on Social Media..         

How to grow Onions in the Garden

Getting the best from Seeds or Sets

Harvesting Onions

Onion Set Growing times

Onions can be grown two ways, from Seed or pre-prepared Onion Sets. Although it may appear to go against my frugal grain, I prefer Sets solely on the grounds that should my seeding not go to plan I may miss the boat !

From Seed

Early varieties ahould be sown when the temperature is above 13 degrees, it's therefore a good idea to sow under Glass.
Sow thinly in boxes then when the seedlings are around 2" - 3" tall pot them up into 4" pots or hardening off with a view to plant out mid-April.
For maincrop you can sow directly to the soil in drills half an inch deep mid March time.
The soil should be finely raked then firmed down well.

From Sets

These are brought from most Gardening Shops from the end of January and can be planted out as soon as the weather and soil seem suitable. Most people leave this until March.
The Onions should be placed 4" to 6" apart depending upon variety and in rows 12" apart.
The sets should be buried so the tops are just under the surface.

Onion Sets


Regular hoeing to reduce weeds is required, a job which requires patience and a good back! Growing them in raised beds will help though.

When the Onions appear to have reached a good size and growing has slowed down, bend over the tops. This helps the sun to mature the Onions better


Onions are a what you see is what you get Vegetable, you'll know when the right time to lift them is solely on appearance.
After lifting them dry them out by turning them upside down. If the weather is dry this is best done where they grew. If wet take them into an airy shed or on Greenhouse staging.

Pests and Diseases

Baby plants are subject to attack from Birds, so protect accordingly, I use upside down Bread Baskets but Mesh would be better.
Onion Fly, Eelworm are the two most common forms of attack.

Onions are ideal companion plants for Carrots, brassicas, beets, strawberries, tomatoes and lettuce.Avoid growing near Lentils, they don't get on.


Dates and times given may vary by Region and on the Variety chosen to grow. Please check the Seed Packets for individual guides.

Onions growing beside Lettuce
Onions are a great Companion Plant. Picture shows either side of Lettuce