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

17 Jan 18, Joe Branco (Australia - temperate climate)
Why are brown and white onions sown at different times
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?
29 Oct 18, hamish (New Zealand - cool/mountain climate)
more than likely planted a little too deeply at start warm regards hamish
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 .
01 Dec 17, Mike (Australia - temperate climate)
Read what it says above - it tells you.
14 Nov 17, rob (Australia - temperate climate)
onions are going to seed . Should I pick now or wait till they brown
20 Nov 17, Mike (Australia - cool/mountain climate)
In future pick before they seed or when you first see them starting to seed.
15 Nov 17, Mike (Australia - sub-tropical climate)
Pick them and then leave in the sun for a few days to brown off.
24 Oct 17, Danie (South Africa - Summer rainfall climate)
Why shouldn't onions be planted close to beans and peas?
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?
Showing 181 - 190 of 368 comments

I sow the onions in late January to early March, I prepare a patch in the vegetable garden for this. The stand where the onions will be transplanted to can be prepared in the mean time, If your soil is very heavy, sand can be worked in, as well as gracious amounts of organic fertilizer and ash (from your wood braai) This method give you time to ensure your bed is light and rich when your onions is ready to be transplanted around April. I use a clear plastic covering during coldest of winter months, just to keep the frost off. Hope this help.

- Conradt

Please provide your email address if you are hoping for a reply


All comments are reviewed before displaying on the site, so your posting will not appear immediately

Gardenate App

Put GardenGrow in your pocket. Get our app for iPhone, iPad or Android to add your own plants and record your plantings and harvests

Planting Reminders

Join 60,000+ gardeners who already use GardenGrow and subscribe to the free GardenGrow planting reminders email newsletter.


Home | Vegetables and herbs to plant | Climate zones | About GardenGrow | Contact us | Privacy Policy

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.
We cannot help if you are overrun by giant slugs.