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

08 Apr 11, allan (Australia - temperate climate)
onion seedling have died from the tip down like thay have burnt off . planted two punnets 2/3 lost . Thought it was spraydrift howerver replanted & has started to die back again could it be sheep manure not rotted enough . Think sheep is high in potash would do it
04 Feb 11, stuart (Australia - temperate climate)
plant onions on the winter solstice
01 Mar 11, Brianna (Australia - temperate climate)
I like to plant my onion seedling out on the winter solstice, as they are less inclined to go to seed and more likely to create nice big onions. If they still try and flower I just cut the flower off and bend the whole top over and generally they still create nice bulbs. To do this I start the seeds off in a tray 4-6 weeks before the winter solstice.
07 Nov 10, Gema gonzalez (Australia - sub-tropical climate)
what do they need, phosforos, iron...potasium? please let me know
01 Jan 11, Daniel (Australia - temperate climate)
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
29 Oct 18, Sue Spriggs (Australia - temperate climate)
My onions always go to seed. What am I doing wrong?
27 Oct 10, sharon (Australia - temperate climate)
I live in the Adelaide hills and i have my onions in since May this year they are starting to get flowers on the top and some bulbs are under the ground as i hilled them a couple of time not knowing thay should be on top of the ground. should i take some dirt away as they have very thick stems and bend the tops over to stop them from going to seed or just pull them up.???
12 Aug 10, Mohan (Australia - temperate climate)
I was in India last month and came across white onions. It is said white onions have medicinal properties. Are the seeds available in Sydney.
10 Aug 10, (Australia - sub-tropical climate)
hello I am a bit confused about the soil.CanI use blood and bone before planting the seedlingsas Iam getting conflicting reports what has worked for you to get the best results
12 Jul 10, Sue Summers (Australia - temperate climate)
I live in the Bass Strait Islands north of Tassie, I want to know the best onions to plant for making pickled onions (brown variety). Also how do I know when to harvest them?
Showing 331 - 340 of 368 comments

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

- Allan Kevin Marshall

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.