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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28 Dec 14, Jan Bruinsma (Australia - sub-tropical climate)
I have 2 onions that have sprouted can I plant them? What can I plant at this time of the year? I am just starting and do not know much. Any help would be appreciated.
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10 Nov 14, Donita (South Africa - Summer rainfall climate)
Hi, when onion leaves start making a flowers, what does that mean? Thanks
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14 Oct 14, Ralph (Australia - temperate climate)
I put a whole red onion into my "garden" about 2mths ago. Now have 5 long stems with what look like flower buds and grass like foliage. Do I separate the stems and replant? Any advice greatly appreciated.
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10 Jan 15, Maurice (Australia - temperate climate)
Most onions are biennial, they flower and die in the second year. With yours I say leave them where they are, let the flower, collect the hundreds of seeds they produce and plant them. We grow a lot of perennial onions like tree onions and potato onions. We got them through the post from mudflower blogspot. They have a lot of perennial vegetables which are much simpler to grow than the regular types.
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27 Sep 14, Deeanna (Australia - temperate climate)
I am a new gardener but I have to live with possums, bush turkeys, mice and wallabies. It has been my experience over the last 4 years that both possums and wallabies would be the culprit eating your onion tips. We cover ours with bird netting. This leaves us with the wallabies that push against the netting to nibble. But they do not get to eat much once the garden is covered securely.
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21 Sep 14, Sarina (Australia - temperate climate)
Our onions (brown and red) are hanging on the fence in a planter box we made from pallets(we have a dog who likes to knock things over). However something is eating the tips of the leaves and only the tips. It wouldn't be possums as the dog would be going crazy. There is no bugs at all near the plants. The fence is colourbond steel, in off-white, and we can not see any trails, marks, tell tale signs of any slugs or snails etc. there is no bugs or sign of them in or around the pallets, and the boxes are lined with weed mat to stop the dirt from falling out. Any ideas of what this could be that's loving the tops of the onions? It's our first ever attempt at growing veggies, and we would really like some to survive!
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29 Aug 15, Sally-Anne Pucek (Australia - temperate climate)
I discovered our cat was nibbling the tips of our young garlic and onions...
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02 Apr 15, (Australia - sub-tropical climate)
Hi there had the same problem and found it was rats ,if you can move them onions to a less easily accessible spot for rats anyway .A fence is like a rat highway
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09 Dec 14, Glen (Australia - sub-tropical climate)
Sounds to me like heat transfer from the tin fence. Regards
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08 Sep 14, Freckson Tineyi Ropi (South Africa - Summer rainfall climate)
I want to buy king onion seed where can l buy it. Am in Limpopo Province
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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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