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

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17 Jan 18, Joe Branco (Australia - temperate climate)
Why are brown and white onions sown at different times
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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?
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29 Oct 18, hamish (New Zealand - cool/mountain climate)
more than likely planted a little too deeply at start warm regards hamish
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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 .
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01 Dec 17, Mike (Australia - temperate climate)
Read what it says above - it tells you.
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14 Nov 17, rob (Australia - temperate climate)
onions are going to seed . Should I pick now or wait till they brown
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20 Nov 17, Mike (Australia - cool/mountain climate)
In future pick before they seed or when you first see them starting to seed.
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15 Nov 17, Mike (Australia - sub-tropical climate)
Pick them and then leave in the sun for a few days to brown off.
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24 Oct 17, Danie (South Africa - Summer rainfall climate)
Why shouldn't onions be planted close to beans and peas?
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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?
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Showing 191 - 200 of 378 comments
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Absolutely! We do all the time! We always cut the onions we buy horizontally in half when cooking and carefully peel down to the middle chunks where you can see how many "dots" are gonna be onions next year. We have a big patch of sandy loose soil that has a lot of chicken manure and/or compost here or there that we plant all of them in. We plant them an inch or so under the soil (totally covered up is best but not too deep) and we do not break them apart first. They grow into BIG beautiful onions in a year or so if you give 'em a drink of water when its dry for weeks. AND they make seeds too! Good seeds if you let them dry all the way out! We love getting free food from cooking scraps... with a bit of pre-planning on slicing the onions right to begin with... Try replanting carrot tops if you want fresh seeds... the top 2" of a regular carrot grows into fluffy foliage and sends up nice fresh seed heads in late summer. Freebies are fun!

- Melinda Schwab

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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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