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

04 Jan 09, Jay (Australia - cool/mountain climate)
I have just pinched out the seed heads on a few that have formed. We are using them fresh from the ground right now, and are waiting for them to die back before lifting. First time onion grower, but am wrapped with the ease of growing and the harvest. All 150+ seedlings have produced 2 - 4" bulbs. Used seed trays for seed, them planted out at 5" spacing. No loses, and NO THINNING (I hate that bit!!!m lol re: carrots) Cheers!
09 Jan 09, stewart (Australia - cool/mountain climate)
Discovered onions growing (planted by previous owner of property) so I dug some up (brilliant white). All sizes and some throwing new ones off the roots?Cut a larger one up to find only about 4 layers and then solid onion? What's the go? Is this about storing and then they develop the other layers? I've not grown them before so have no idea.
14 Mar 09, Ferolyn (Australia - temperate climate)
I found a forgotten red onion in my cupboard few months ago and it already has aboiut 3inches of shoot. I planted it. Now I have a tall stem of about almost 3feet with a pretty pompom flower on it. Would i still have onion out of it? It now has little pids on the pompom. I broke one of its pods out of curiosity and it has little black round bits inside... is that the seed? Would i get onions if i plant those seeds?
15 Mar 09, Evelyn (Australia - cool/mountain climate)
I was wondering if it is too late to plant onions now in Canberra. I believe day length is the key but not sure which ones are which. Any assistance appreciated. PS. I have never grown onions before.
15 Mar 09, Graeme (Australia - temperate climate)
I have grown onions from seed and bought seedlings for years, but they always "bolt" and run to seed. What is the secret to growing them successfully? I don't want to give up just yet, but I am getting frustrated. I live in Melbourne which I think is classed as temperate
16 Mar 09, David (Australia - temperate climate)
Ferolyn: The black (sharp) bits in the "pom-pom" are seeds. Yes you will get onions off them if you plant them. No, once the Onion has flowered it is pretty useless as an onion. Evelyn: day length sets teh onions "growing' it's bulb. you need the onion plant to grow in height BEFORE it grows its bulb else you end up with "sort of" spring onions. In canberra with heavy frosts probably better to wait til mid winter before planting. Graeme: timing is the key. If you live near the bay then you should be good to plant mid-late april (depending on the variety) this will allow the plant to grow before it starts bulbing (longer days). I planted Hunter River Browns today (West Sydney) so I am expecting a harvest of HUGE onions Nov-Dec
18 Apr 09, Gervaise (Australia - temperate climate)
where can i find onion sets for spring planting...not seed but the actual bulb...im in NSW...?
23 Apr 09, Evelyn (Australia - cool/mountain climate)
Evelyn, I live in a cool mountain area with frosty winters. I sow onions successively from March through to August. I like to grow long keepers, Creamgold being my favourite as I have kept them for up to six months (ate them all by then so don't know how long they keep). I have also sown Ailsa Craig for the first time this year and would be interested to hear feedback from anyone who has grown that variety.
29 Jun 09, Mel (Australia - cool/mountain climate)
i am interested in planting onions, does this chart shown about growing months occur to Australia?
27 Jul 09, Barb (Australia - sub-tropical climate)
Hi Mel, if you select the climate zone for your area in Australia, then the planting guide will tell you which months you can plant onions in your area.
Showing 11 - 20 of 358 comments

Hi, I’m having fun growing potatoes, Kumara and even sweetcorn that have sprouted in the bottom of my pantry. Wondering if the same should work with a brown onion that has sprouted greens out of the top?

- Leigh

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.