Growing Onion

Allium cepa : Amaryllidaceae / the onion family

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

06 May 17, Sean (Australia - sub-tropical climate)
Onion seedlings from punnets are usually very small.Make a V shaped trench abut 50 mm (2") deep and lay them along one side of the trench at recommended spacing (probably 100 mm (4") then carefully draw the soil from the other side of the trench over the base of the seedlings. This is best done on a cool overcast day or in the evening as a warm sunny day will stress the little seedlings too much. They might stay laying down for a few days but will soon be upright.
22 Apr 17, Keikantseng (South Africa - Summer rainfall climate)
I an staying in Taunton village in North west province. Can I plant onion in April?
23 Apr 17, John (Australia - temperate climate)
Yes you can. Long Keeping varieties can be sown now.
18 Apr 17, gayle (Australia - temperate climate)
Hi...I have planted brown onion seeds in seed trays a week ago..they are sprouting...I was wondering when do I plant them in the vegetable garden. Also can I plant seed potatoes now (April) in Victoria. Thanks.
19 Apr 17, Giovanni (Australia - temperate climate)
Onion seedlings are susceptible to danping off so make sure they are in a well aired place. They can be transplanted as soon as they are large enough (2 or 3 leaves). The smaller they are the more attention they will need in the ground so wait a while, they will be easier to transplant and with less transplanting shock.
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
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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. 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.
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