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

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/
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.
25 Oct 09, mick (Australia - temperate climate)
hi i use to grow hunter river white onions and just cant find where i can buy seed anymore .I live in the wollindilly distric ?
16 Jan 10, Fritz (Australia - temperate climate)
My Brown Onions seem to be ready to harvest.How do I store them? What is a cool Place ? Do i keep them in the Fridge or just in the Kitchen cubboard? In Paper Bags/
17 Apr 10, Chris (Australia - cool/mountain climate)
Fritz - a cool place for storing onions is in a bottom cupboard or similar. Anywhere that doesn't get hot. They tend to go mouldy in a fridge
12 Jul 10, Sue Summers (Australia - temperate climate)
I live in the Bass Strait Islands north of Tassie, I want to know the best onions to plant for making pickled onions (brown variety). Also how do I know when to harvest them?
27 Oct 10, sharon (Australia - temperate climate)
I live in the Adelaide hills and i have my onions in since May this year they are starting to get flowers on the top and some bulbs are under the ground as i hilled them a couple of time not knowing thay should be on top of the ground. should i take some dirt away as they have very thick stems and bend the tops over to stop them from going to seed or just pull them up.???
07 Nov 10, Gema gonzalez (Australia - sub-tropical climate)
what do they need, phosforos, iron...potasium? please let me know
01 Jan 11, Daniel (Australia - temperate climate)
Onions need a fairly mellow compost. The best conditions to grow onions in would be to have a very rich composted bed which you grow something like tomatoes or zucchinis in (heavy feeders) and once those summer crop are finished plant onions in to that same soil. That will give you the best onion results. Onions also require a cold period to form the bulb
29 Oct 18, Sue Spriggs (Australia - temperate climate)
My onions always go to seed. What am I doing wrong?
Showing 21 - 30 of 192 comments

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