Growing Onion

Allium cepa : Amaryllidaceae / the onion family

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

(Best months for growing Onion in Australia - sub-tropical regions)

  • S = Plant undercover in seed trays
  • T = Plant out (transplant) seedlings
  • 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 8°C and 30°C. (Show °F/in)
  • Space plants: 5 - 10 cm 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

04 May 17, Paul (Australia - temperate climate)
How deep do you plant the onion seedling if you buy a small tray from a garden centre or Bunnings?
06 May 17, Sean (Australia - sub-tropical climate)
Onion seedlings from punnets are usually very small.Make a V shaped trench abut 50 mm (2") deep and lay them along one side of the trench at recommended spacing (probably 100 mm (4") then carefully draw the soil from the other side of the trench over the base of the seedlings. This is best done on a cool overcast day or in the evening as a warm sunny day will stress the little seedlings too much. They might stay laying down for a few days but will soon be upright.
18 Apr 17, gayle (Australia - temperate climate)
Hi...I have planted brown onion seeds in seed trays a week ago..they are sprouting...I was wondering when do I plant them in the vegetable garden. Also can I plant seed potatoes now (April) in Victoria. Thanks.
19 Apr 17, Giovanni (Australia - temperate climate)
Onion seedlings are susceptible to danping off so make sure they are in a well aired place. They can be transplanted as soon as they are large enough (2 or 3 leaves). The smaller they are the more attention they will need in the ground so wait a while, they will be easier to transplant and with less transplanting shock.
15 Apr 17, Jack (Australia - sub-tropical climate)
I've been looking for white onions for some time . Is there any reason for the short supply ?
15 Apr 17, Jo (Australia - temperate climate)
Do you mean white long-keeper, or white salad onions. Both types should be readily available on-line from companies like - New Gippsland Seeds, The Seed Collection, Diggers, Green Harvest and Eden seeds.
08 Apr 17, Sandra Millhouse (Australia - temperate climate)
Why are my brown onions growing up as spring onions?? I have even rung the company of the seeds and they sent me two new packets of seeds out. I planted some of them and they are still coming up as spring onions. Please help
11 Apr 17, David (Australia - temperate climate)
Onions take 4, 5 ,6 months to form the onion bulb. You may be expecting them too soon. I plant early Barletta onions March\April and Australian Brown, or Creamgold June to Sept. They look like spring onions until they form the bulb.
09 Apr 17, Giovanni (Australia - sub-tropical climate)
There are a number of reasons that could contribute to your problem with brown onions. 1. have you planted the right variety for the time of the year? Brown onion seed is normally sown in April or May. There a range of planting times for different types of onion. 2. Have you planted them too close? Onions will take some time before they 'bulb' out and may be still in the 'juvenile' stage. 3. Are they getting plenty of sun?. It is a difficult question to answer but as you have replanted seed it is not that. Trust this helps.
25 Feb 17, Eric ryan (Australia - temperate climate)
Can I grow onion in Hervey bay qld the sweet variety preferably
Showing 71 - 80 of 192 comments

Why are my brown onions growing up as spring onions?? I have even rung the company of the seeds and they sent me two new packets of seeds out. I planted some of them and they are still coming up as spring onions. Please help

- Sandra Millhouse

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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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