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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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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23 Oct 21, Judy (Australia - temperate climate)
My onions are starting to go to seed. Why has this happened, and what can I do about it?
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10 Oct 21, jim (New Zealand - temperate climate)
I am interested in planting dates for onions all my seed packets put planting in late autum winter but they are differen on this site.My father always planted onion sets are they available in NZ
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13 Oct 21, Anon (New Zealand - temperate climate)
The guide here is only a guide subject to your local conditions. You could try planting now.
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11 Oct 21, Sassy (USA - Zone 9b climate)
Jim, you just missed the spring planting season, ending in September. You can sow seed starts, in doors, under grow lights, in February to transplant in April or direct sow in May. The spring planting season begins with sowing starts in Jun, transplanting in August, or direct sowing in September. You can find this information in the Vegetable and Herb tab, click on Onion, select your Climate Zone and look at the coded calendar. Good luck with your onions next Fall.
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05 Jul 21, Jacqueline (Australia - temperate climate)
I'm interested in planting red onions, I am growing spring onions, and leeks quite successfully but know nothing about red onion planting and care. Could you please advise me. I only have a small balcony style garden.
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10 Jul 21, (Australia - sub-tropical climate)
All the onion family are pretty similar to grow. Plant them similar time as spring onions and leeks. If you want more info google
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08 Aug 21, anne onn (Australia - temperate climate)
telling people to google something on a plant website is just lazy. @Jacqueline, you can safely plant the red onions as if they were spring onions, just allow for more space between the plants Note: Gardenate does not advise google - we assume that is how the questioner found our site)
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two questions. Which variety of onions and garlic are best for growth in Puerto Rico. were can I buy them and expect to get them to Puerto Rico. Many say they are not to be shipped to Puerto Rico(price for living in the colony). Thanks, C.Foy

- Clifford Foy

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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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