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

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08 Feb 13, Jase (Australia - cool/mountain climate)
Onions are immortal and can be re-planted after harvest. When cutting for food, chop <1.5 cm from the roots for re-planting. Water well and the onion will bulb into a few new plants. Separate the bulbs and you will have a new batch of onions.
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20 Apr 12, (Australia - cool/mountain climate)
I must be very lucky! I ignored everything the onion pack said (like covering with seed raising mixture, etc) and planted the seeds right into the dirt. Rather than the seeds taking 21-28 days as the packet said, they came through in 10 and going really strong :) All the best :)
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01 Feb 12, greg (South Africa - Humid sub-tropical climate)
Can u pls provide me informations on onion cultivation in my area
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13 Jan 12, Narelle (Australia - temperate climate)
How do you get onion seeds to germinate? I've tried with a few different seed packets, but no luck. Is it the soil? I'd love some information for optimum conditions for growing onions from seed.
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05 Feb 12, Jimmy (Australia - temperate climate)
I raised seeds in seed propogating mix in small containers first. That way I can control watering and temperature better until they are strong enough to transplant. Have had almost 100% seed germination rate so far! Hope that helps.
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03 Nov 11, (Australia - sub-tropical climate)
can i plant brown onions now we are nearly at the end of spring
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26 Jul 11, (Australia - sub-tropical climate)
How do I plant a onion that has already started to shoot
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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.
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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).
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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
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Showing 151 - 160 of 192 comments
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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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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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