Growing Onion

Allium cepa : Amaryllidaceae / the onion family

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

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

  • S = Plant undercover in seed trays
  • T = Plant out (transplant) seedlings
  • 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

07 Oct 09, Annie (Australia - sub-tropical climate)
I have the same issue as Kate. My onions are looking great, getting bulbs. I don't want to wait too late in case they start bolting. But I don't know when to harvest them. Or to bend the stems over or just pull them, which is what I've done before. They still have thick stems.
02 Oct 09, Kate (Australia - temperate climate)
My onions have now got flower pods at the top but never really got round at the bottom like an onion should. Everything says wait till the stems fall over and dry out but I also saw that when they flower they are no good. Help I am confused as to what to do. Do I just pull them all out and plant something else?
05 Mar 18, David (Australia - temperate climate)
Kate This happened to me too the first year I planted onions. Then after reading more I found that an onion grows to reproduce. It has two choices: 1. To flower. If it does then all it’s energy will pass from its bulb to the flower. Result no onion but a nice flower. 2. To form a bulb and wait for another year. This is what happpens when you bend the tops over and tie back the flower scape so it does not grow. When this is done, the onion stops putting energy into the flower and concentrates on forming a bulb. Then you get an onion. They are quite persistent so you will need to keep the tops bent over once the leaves start to brown. So plant as normal. Then when the tops start to brown bend them over and tie back the head so as to prevent or stop the flowering. https://garden.org/frogs/view/7543/
08 Sep 09, Ani (Australia - cool/mountain climate)
Hi, Just wondering, is there any chance you can put an onion that has started shooting roots in water and have it grow? Thanks.
11 Aug 09, (Australia - temperate climate)
I have geown onions for sometime with very ittle success, why don't the bulbs swell?
27 Jul 09, Barb (Australia - sub-tropical climate)
Hi Mel, if you select the climate zone for your area in Australia, then the planting guide will tell you which months you can plant onions in your area.
29 Jun 09, Mel (Australia - cool/mountain climate)
i am interested in planting onions, does this chart shown about growing months occur to Australia?
23 Apr 09, Evelyn (Australia - cool/mountain climate)
Evelyn, I live in a cool mountain area with frosty winters. I sow onions successively from March through to August. I like to grow long keepers, Creamgold being my favourite as I have kept them for up to six months (ate them all by then so don't know how long they keep). I have also sown Ailsa Craig for the first time this year and would be interested to hear feedback from anyone who has grown that variety.
18 Apr 09, Gervaise (Australia - temperate climate)
where can i find onion sets for spring planting...not seed but the actual bulb...im in NSW...?
16 Mar 09, David (Australia - temperate climate)
Ferolyn: The black (sharp) bits in the "pom-pom" are seeds. Yes you will get onions off them if you plant them. No, once the Onion has flowered it is pretty useless as an onion. Evelyn: day length sets teh onions "growing' it's bulb. you need the onion plant to grow in height BEFORE it grows its bulb else you end up with "sort of" spring onions. In canberra with heavy frosts probably better to wait til mid winter before planting. Graeme: timing is the key. If you live near the bay then you should be good to plant mid-late april (depending on the variety) this will allow the plant to grow before it starts bulbing (longer days). I planted Hunter River Browns today (West Sydney) so I am expecting a harvest of HUGE onions Nov-Dec
Showing 171 - 180 of 192 comments

I have the same issue as Kate. My onions are looking great, getting bulbs. I don't want to wait too late in case they start bolting. But I don't know when to harvest them. Or to bend the stems over or just pull them, which is what I've done before. They still have thick stems.

- Annie

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