Keep your garden growing - see what to plant right now

Growing Onion

Jan F M A M J J A S O N Dec
  S P P                

(Best months for growing Onion in USA - Zone 5a regions)

S = Plant undercover in seed trays 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

15 Apr 17, Jack (Australia - sub-tropical climate)
I've been looking for white onions for some time . Is there any reason for the short supply ?
15 Apr 17, Jo (Australia - temperate climate)
Do you mean white long-keeper, or white salad onions. Both types should be readily available on-line from companies like - New Gippsland Seeds, The Seed Collection, Diggers, Green Harvest and Eden seeds.
11 Apr 17, nik (New Zealand - temperate climate)
I planted 50 red onion seedling last year and they all split into 3 or 4 more like shallots, so after 6 months I gave up and pulled them out What went wrong ? there is no red shallot variety is there?
11 Apr 17, John (Australia - sub-tropical climate)
Onions are like daffodils and other bulbs in that they will grow extra bulbs as a form of multiplication. This can be caused by planting at the wrong time of the year for the variety. Check this on the seed packet and plant accordingly. Sadly nurseries sometimes sell 'out of season 'plants that look good. Tomatoes are a classic example with many plants sold after a few sunny days in late Winter or Early Spring. Trust this helps.
08 Apr 17, Sandra Millhouse (Australia - temperate climate)
Why are my brown onions growing up as spring onions?? I have even rung the company of the seeds and they sent me two new packets of seeds out. I planted some of them and they are still coming up as spring onions. Please help
11 Apr 17, David (Australia - temperate climate)
Onions take 4, 5 ,6 months to form the onion bulb. You may be expecting them too soon. I plant early Barletta onions March\April and Australian Brown, or Creamgold June to Sept. They look like spring onions until they form the bulb.
09 Apr 17, Giovanni (Australia - sub-tropical climate)
There are a number of reasons that could contribute to your problem with brown onions. 1. have you planted the right variety for the time of the year? Brown onion seed is normally sown in April or May. There a range of planting times for different types of onion. 2. Have you planted them too close? Onions will take some time before they 'bulb' out and may be still in the 'juvenile' stage. 3. Are they getting plenty of sun?. It is a difficult question to answer but as you have replanted seed it is not that. Trust this helps.
18 Mar 17, irene (South Africa - Semi-arid climate)
every i plant onion they dont come out what can i do plss help or tips.
21 Mar 17, John (Australia - temperate climate)
Onions are generally fairly easy to germinate. They need to be planted about 3 times their diameter with soil. A good way to do this is to sprinkle the seed over a small area that has been broken up and is very fine then cover with some more fine soil. Keep the soil damp but not wet. When the seedlings emerge they will be very fine like a needle. keep them damp but not wet as they may get fungus problems. A spot that gets some sunshine and a bit of airflow is good. They will take about 4-6 weeks before they are ready to transplant into rows in the garden. They will take about 6 months to be ready to harvest and store (when the tops flop over and start to dry). I hope this helps. Don't hesitate to ask questions, we are here to help.
25 Feb 17, Eric ryan (Australia - temperate climate)
Can I grow onion in Hervey bay qld the sweet variety preferably
Showing 21 - 30 of 176 comments

Post a question, comment or tip about Onion

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

Buy the app for iPhone/iPod, iPad or Android and support Gardenate

Planting reminders

Join 30,000+ gardeners who rely on Gardenate. Subscribe to our free planting reminders email newsletter


Home | Vegetables and herbs to plant | Climate zones | About Gardenate | 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. Gardenate 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.