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 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

26 Jul 11, (Australia - sub-tropical climate)
How do I plant a onion that has already started to shoot
31 Jul 11, Karen (Australia - temperate climate)
with the green shoot just out of the ground - bulb covered with soil. Do not over water or you will have mush.
01 Jun 11, arthur (Australia - temperate climate)
I find the best way to store onions pull them, leave them exposed on top of the ground for two days or until the are brown then platt them like they do in spain. Hang if possible from roof of a shed or such like. ( arthur the mad gardner).
08 Apr 11, allan (Australia - temperate climate)
onion seedling have died from the tip down like thay have burnt off . planted two punnets 2/3 lost . Thought it was spraydrift howerver replanted & has started to die back again could it be sheep manure not rotted enough . Think sheep is high in potash would do it
04 Feb 11, stuart (Australia - temperate climate)
plant onions on the winter solstice
01 Mar 11, Brianna (Australia - temperate climate)
I like to plant my onion seedling out on the winter solstice, as they are less inclined to go to seed and more likely to create nice big onions. If they still try and flower I just cut the flower off and bend the whole top over and generally they still create nice bulbs. To do this I start the seeds off in a tray 4-6 weeks before the winter solstice.
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?
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.???
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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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