Growing Onion

Allium cepa : Amaryllidaceae / the onion family

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

(Best months for growing Onion in USA - Zone 7a regions)

  • 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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11 Aug 09, (Australia - temperate climate)
I have geown onions for sometime with very ittle success, why don't the bulbs swell?
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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.
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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?
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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/
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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.
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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 ?
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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/
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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
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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?
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10 Aug 10, (Australia - sub-tropical climate)
hello I am a bit confused about the soil.CanI use blood and bone before planting the seedlingsas Iam getting conflicting reports what has worked for you to get the best results
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Showing 21 - 30 of 369 comments
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I'm about to start growing onions from seeds and it says keep them under cover until early spring when they are ready to be planted out, I'm just wondering exactly what undercover means. Does it mean inside undercover or just out of direct sunlight outside. "Undercover" is very vague and I don't want to mess these up.

- Paris

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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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