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

05 Mar 21, (Australia - sub-tropical climate)
Brown onions keep better than white onions. Let them harden off a bit after picking and keep in a cool aeriated area. Don't pack them tight - like in a bag.
26 Feb 21, Greg J (Australia - temperate climate)
Geelong Australia. I pulled up a couple of beds of brown onions in November. They've been hanging in the back shed since then, no problems at all. They're still as good as when I pulled them up, and we've been using them slowly. I think they will easily last 6 months or more.]
25 Feb 21, Brad (Australia - sub-tropical climate)
Depends on the variety of brown onion mate, the more pungent ones will store longer but they are more suitable to cooler areas. I'm sub-tropical too i'm from brisbane and I do a variety call "Texas early granno" I pulled about 70 to 80 out last year and none went bad. The trick is to harvest them when you need them. Green Harvest is a great site where I get most of my seeds from they are situated in south-east Qld and they have a lot of info of different varieties and the climates they are best suited for. Hope that helped Brett. -Brad
16 Feb 21, Judith c Greenleaf (USA - Zone 9b climate)
Can I plant onion sets in February or march? what sweet onion varieties do you suggest for No. Ca. marine zone 9B? Thank you.
17 Feb 21, Anonymous (USA - Zone 9b climate)
Consult the planting guide calendar and the footnote at the bottom of the page. If it says plant April and you plant Feb, the seeds/sets probably won't germinate/survive . There are reasons why it says to wait until April but take local conditions into considerations.
12 Feb 21, Rosie (Canada - Zone 5b Temperate Warm Summer climate)
How do you care for onion plants: weeding, cutting back,spooning,fertilizing,watering?
02 Mar 21, (Canada - Zone 5a Temperate Warm Summer climate)
Start with good loose soil that has had some fertiliser, compost, manure put in it, don't over do it though. Water every day when small and then each 2 days when half grown. Keep weeded.
03 Feb 21, Sky Kell (USA - Zone 7b climate)
Perennial onion that multiplies for 7b zone
18 Dec 20, Sydney Thama (South Africa - Summer rainfall climate)
hello it is safe to plant onion around July and August?
21 Dec 20, Anon (South Africa - Summer rainfall climate)
Go the onion page and check when to plant onions in your climate zone, or google and research about growing onions.
Showing 11 - 20 of 282 comments

Some of my creamgold and red onions are shooting to seed. Some have large healthy bulbs. Should I harvest them now?? Others have virtually no bulb. Can I cut the seed head off and let them continue to develop?

- Steve

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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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