Growing Onion

Allium cepa : Amaryllidaceae / the onion family

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

(Best months for growing Onion in New Zealand - cool/mountain regions)

  • S = Plant undercover in seed trays
  • T = Plant out (transplant) seedlings
  • 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

Post a comment or question Display Newest first | Oldest first, Show comments for New Zealand | for all countries
04 Dec 17, andrew heaps (New Zealand - temperate climate)
hi,my onions have thick stalks just above the onions them selves.is that normal?and if not what is the remedy?
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29 Oct 18, hamish (New Zealand - cool/mountain climate)
more than likely planted a little too deeply at start warm regards hamish
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27 Nov 17, John (Australia - temperate climate)
Hello and thanks for your time I would like to grow red onions i live in the wrstarn suburbs of Adelaide when do I plant seed thank you .
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01 Dec 17, Mike (Australia - temperate climate)
Read what it says above - it tells you.
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14 Nov 17, rob (Australia - temperate climate)
onions are going to seed . Should I pick now or wait till they brown
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20 Nov 17, Mike (Australia - cool/mountain climate)
In future pick before they seed or when you first see them starting to seed.
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15 Nov 17, Mike (Australia - sub-tropical climate)
Pick them and then leave in the sun for a few days to brown off.
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24 Oct 17, Danie (South Africa - Summer rainfall climate)
Why shouldn't onions be planted close to beans and peas?
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17 Oct 17, Danie (South Africa - Summer rainfall climate)
Do I have to roll the leaves of the plants to enhance bulb forming at this time before they are harvested to prevent new growth?
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04 Oct 17, Vincent Mulenga (South Africa - Summer rainfall climate)
I'm in Zambia can I grow onion rainfall whan should I plant my ?
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Showing 191 - 200 of 377 comments
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Onions are generally fairly easy to germinate. They need to be planted about 3 times their diameter with soil. A good way to do this is to sprinkle the seed over a small area that has been broken up and is very fine then cover with some more fine soil. Keep the soil damp but not wet. When the seedlings emerge they will be very fine like a needle. keep them damp but not wet as they may get fungus problems. A spot that gets some sunshine and a bit of airflow is good. They will take about 4-6 weeks before they are ready to transplant into rows in the garden. They will take about 6 months to be ready to harvest and store (when the tops flop over and start to dry). I hope this helps. Don't hesitate to ask questions, we are here to help.

- John

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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. GardenGrow 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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