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 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

13 Oct 21, Anon (New Zealand - temperate climate)
The guide here is only a guide subject to your local conditions. You could try planting now.
20 Jun 23, Sue (New Zealand - temperate climate)
My onions got a rusty fungus on the last year how do I guard against this happening again. I grew the multiplying onions found them in the garden centre as Welsh Onions. They were great until they developed the fungus.
24 Jun 23, jim (New Zealand - temperate climate)
Copper copper copper I had same problem last year onions,garlic and leeks sometimes gardening is a pain but I still do it ??? Remember to use a sticker "sprayfix" by yates is one but most garden chemical people do similar it helps to break down the surface tension so the spray does not just run off do it before it appears and repeat it several times during the season only problem with it raining constantly it's hard to do right now. P.S. my mum used to grow welsh onions in the UK when I was a boy never saw enything like rust ?
09 Dec 23, Gill (New Zealand - temperate climate)
How much watering do onions like. On tank water so hoping not heavy drinkers
14 Dec 23, (New Zealand - sub-tropical climate)
Just give a watering 2-3 times a week depending on how hot it is.
Showing 31 - 35 of 35 comments

My onions growing in Napier are sprouting seed heads. Some are large seeming perhaps fully grown or close but some aren�t. Should I nip the heads and leave them or pull them immediately?

- 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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