Growing Onion

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

(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

12 May 20, Anon (South Africa - Semi-arid climate)
Check the top of the page .
08 Apr 20, Harpreet Kaur (New Zealand - cool/mountain climate)
If you sow seeds of red onion indoor in April and wait till it can be transplanted outside..say in June.. Can it stay in the ground in cold winters harmlessly..n mature in summers to come around Christmas? Or will it die in cold weather buried in soil ?
09 Apr 20, anonymous (New Zealand - cool/mountain climate)
Go to cool/mountain NZ look up onion and look at the monthly calendar at the top of the page - read what S P &T mean and then apply that to your question.
01 Apr 20, paul ryan (Australia - temperate climate)
What do you mean by saying onion bulbs should sit on the soil and not be covered.
03 Apr 20, Anon (Australia - sub-tropical climate)
When an onion grows the bulb part sits on top of the soil, only the roots are in the soil. DO NOT hill the soil up over the bulb. Check on the internet and see.
01 Apr 20, Kaz (USA - Zone 11b climate)
Aloha What onions & tomatoes grow well in zone 11 Hawaii Ohau north shore
25 Nov 19, William Rowe (USA - Zone 9b climate)
What variety of onion do you suggest for my region. 9b Ocala,Fl
26 Oct 19, Allan Kevin Marshall (Australia - cool/mountain climate)
I sowed my Hunter River Brown seeds on the 1st of April in rows East & West I thinned them out & the thinnings I planted in a bed facing North & South .The thinnings are bolting to seed,& the ones planted in the East West are doing well. I live in Geelong Victoria,What could be the fault here with the planting North & South
08 Dec 19, Susan in Canberra (Australia - temperate climate)
Hi Allan, is it possible that the thinnings were stressed by being pulled out & replanted and this caused them to bolt ahead of the original plantings?
28 Oct 19, anon (Australia - sub-tropical climate)
My home garden is NS and a men's shed gardens I had were NS. I'm now in a new garden set up that is EW. I have wondered about the difference. My thoughts are with the plantings NS, ALL plants have sun on them all the day whatever hours that is. The sun from the E in the morning and W in the afternoon. With the EW some plants might be shaded by other plants during the day. Different beds could be different soil fertility, hrs of sunlight, watering etc. Generally when soil nutrient and/or water are not sufficient the plant will flower and set seed to be able to reproduce in the future.
Showing 11 - 20 of 252 comments

I just planted onions that got spoiled and started to grow but now each bulb has grown into a set of seedlings. Do I pull them out and plant them separately or leave them grow as they are? Kind Regards Sam

- Sam

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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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