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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21 Apr 16, Karina (Australia - sub-tropical climate)
Hi I've planted onion seeds directly into the garden bed and then mulched over the top. Should I have waited until the seedlings grew before mulching? I've heard that like carrots you are supposed to thin them out? What should I do? TIA
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30 Apr 16, Paul (Australia - arid climate)
Mulching over seed will not allow them to germinate and then push through to the sun. Onion, lettuce and carrot all grow well together (The Three Sisters) and need to "see the sun" to germinate well. I plant the three mixed together thrown over the bed and then water in stirring the top 5mm of soil in the process and then keep moist with a misting rosehead. They will then come up thicker than hairs on a cats back and effectively do not need mulch until you have thinned out the baby carrots to allow bigger ones to grow. Lettuce you can pick and let come again while the onions slowly get bigger. Trim dead and yellowing onion leaves to encourage more growth.
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11 Apr 16, theresa (Australia - temperate climate)
Which variety red, white, brown onions seedlings ,when to plant as I understand they are planted at different times to minimize bolting. Thanks
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06 Feb 16, barry rowcliffe (Australia - cool/mountain climate)
do mealybug in the ground effect onions,if so what remedy is there. thanks
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22 Jan 16, Heidi (Australia - temperate climate)
I have several onions that are sprouting. Can I plant them now? Our temperatures are very high in summer so they might not survive, but they won't keep until autumn.
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09 Oct 15, graham paul (Australia - temperate climate)
how do you grow pickling onions I have sown brown onions, regards graham
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02 Oct 15, Fred Spiegel (Australia - temperate climate)
What is the diference between a onion and a salad onion
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23 Apr 15, mark (Australia - sub-tropical climate)
what is the best type of onions to grow around coastial areas ie Brisbane Cleveland area
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28 Dec 14, Jan Bruinsma (Australia - sub-tropical climate)
I have 2 onions that have sprouted can I plant them? What can I plant at this time of the year? I am just starting and do not know much. Any help would be appreciated.
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14 Oct 14, Ralph (Australia - temperate climate)
I put a whole red onion into my "garden" about 2mths ago. Now have 5 long stems with what look like flower buds and grass like foliage. Do I separate the stems and replant? Any advice greatly appreciated.
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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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