Growing Onion

Allium cepa : Amaryllidaceae / the onion family

Jan F M A M J J A S O N Dec
  S                    
    P P                

(Best months for growing Onion in USA - Zone 5a regions)

  • S = Plant undercover in seed trays
  • P = Sow seed
  • Easy to grow. Grow in seed trays, and plant out in 4-6 weeks. Sow seed at a depth approximately three times the diameter of the seed. Best planted at soil temperatures between 46°F and 86°F. (Show °C/cm)
  • Space plants: 2 - 4 inches apart
  • Harvest in 25-34 weeks. Allow onions to dry before storing.
  • Compatible with (can grow beside): Lemon Balm, Borage, Carrots, Beets, Silverbeet, Lettuce, Amaranth
  • Avoid growing close to: Peas, Beans

Your comments and tips

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21 Apr 22, Anonymous (Australia - temperate climate)
I believe they do cross pollinate.
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26 Mar 22, Heidi (Australia - temperate climate)
I have some onion sets left over from last year and want to plant them. All the articles I have seen thus far talk about growing them from seed/seedlings. Ours is a temperate climate, so when is a good time to plant them?
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19 Apr 22, Graham (Australia - temperate climate)
Sets . Another word for seedlings. If they are still fresh and viable they should be OK. In saying that, I am surprised that they are still OK from last year. (Gardenate : 'sets' are usually small onion bulbs with brown, papery skin)
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29 Mar 22, Anonymous (Australia - sub-tropical climate)
Check the top of the onion page.
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21 Feb 22, Narelle (Australia - tropical climate)
Is Mackay too hot to grow onions? What's the best variety for up here? Thanks
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22 Feb 22, (Australia - tropical climate)
Any variety.
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22 Feb 22, Anonymous of Bundaberg (Australia - tropical climate)
Go to onion, set the climate zone to tropical and it will show you in the calendar guide. They take a long time to grow and are generally cheapish in shops.
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30 Nov 21, marco (Australia - tropical climate)
hi i live on the gold coast qld .i have planted onion .rossa lunga di firenze .in late october ,early november .they are there and havent done much .we have had lots of rain here and the onions have thickened up quite a bit .i have thrown more seeds in a tray and i will plant them to see how they grow out .i might be too early yet i will let u know how it pans out !!
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07 Dec 21, Anonymous (Australia - sub-tropical climate)
You are sub-tropical. Click that in SET YOUR CLIMATE ZONE. Then go to onion. You basically plant onions in autumn early winter.
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22 Dec 21, marco (Australia - temperate climate)
yes you are right my onions thickened up with all the rain .yet they stalled in growth again .new seed seeded yet they are thin as well .like u said wrong time of year to grow .i will keep them in the ground to see what happens .(my first year of growing onions)
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Showing 11 - 20 of 193 comments
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One last thought .... I never seem to get everything into my first response ==> Egyptian walking onion --onions and other alliums need more phosphorus and potassium than most other vegetables. They also need more copper, manganese, zinc, and molybdenum- however most of these are adequately represent in compost. BUT, if you have any issues, and it is unlikely that you will with walking onions --- but if you do, first thing I would do is ensure all of these elements are present (in Canada our "old" pennies have a lot of copper, we just add this obsolete currency to the garden). Molybdenum is found in wood ash (just the stuff from the fireplace, firepit or wood burning stove -- provided you have burned "clean wood" )-- probably lots in leaf compost, and banana peel compost)-- of course potassium in potash etc.

- Celeste Archer

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This planting guide is a general reference intended for home gardeners. We recommend that you take into account your local conditions in making planting decisions. Gardenate is not a farming or commercial advisory service. For specific advice, please contact your local plant suppliers, gardening groups, or agricultural department. The information on this site is presented in good faith, but we take no responsibility as to the accuracy of the information provided.
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