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

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.
03 Nov 11, (Australia - sub-tropical climate)
can i plant brown onions now we are nearly at the end of spring
05 Nov 11, wes (New Zealand - sub-tropical climate)
We grew white onoins & have just harvested & are now drying in the sun. How long should they be dried ? Is it better to leave the tops on or should they be cut off to speed drying? Regards,wes.
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.
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.
01 Feb 12, greg (South Africa - Humid sub-tropical climate)
Can u pls provide me informations on onion cultivation in my area
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 :)
05 Jun 12, peggy (USA - Zone 5a climate)
for a better onion do you fold over the tops of the onions when they get tall
10 Mar 14, GJX (USA - Zone 5a climate)
yes, this causes the bulb to get bigger
04 Aug 12, Kevin (Australia - cool/mountain climate)
No. The tops need to fall themselves ideally when they are ready. If the stem is thick and appears to be forming a seed head, then pull them out and eat first.
Showing 41 - 50 of 358 comments

Onions need a fairly mellow compost. The best conditions to grow onions in would be to have a very rich composted bed which you grow something like tomatoes or zucchinis in (heavy feeders) and once those summer crop are finished plant onions in to that same soil. That will give you the best onion results. Onions also require a cold period to form the bulb

- Daniel

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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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