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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19 Oct 20, (South Africa - Summer rainfall climate)
Pull them out.
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10 Sep 20, Vicky (South Africa - Summer rainfall climate)
I planted red onion seedlings in April. I was waiting for the tops to bend over, as I've read. But now they're flowering. When should I have harvested? Also. The necks are very thick.
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11 Sep 20, (South Africa - Summer rainfall climate)
I don't grow onions but it says 24-34 weeks until harvest. It is probably time to harvest if they are going to seed. Pull out and allow to dry.
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01 Sep 20, M.fourie (South Africa - Summer rainfall climate)
My onions grow big but don t have any bulbs.thy were planted from seedlings juni july and grow easy but till now no bulbs.we are in south of namibia
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03 Sep 20, Anonymous (South Africa - Semi-arid climate)
Work out your climate type from the Blue climate Zone tab at the top of the page. Then check the planting guide. You may have planted out of season or at the very end of the season. Usually if something grows really well but doesn't produce a crop your soil is too rich, too much nitrogen.
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24 Jun 20, Jimmy Spear (South Africa - Humid sub-tropical climate)
I planted half of an onion In a pot under potting soil +- 4 weeks ago and it has grown 3 healthy shoots about 20 cm long. What must I do now?? Please advise
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25 Jun 20, (South Africa - Summer rainfall climate)
Keep growing it and see what happens.
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25 May 20, Mlungisi Zwane (South Africa - Summer rainfall climate)
when is the good time/season to plant onion in south africa?
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25 May 20, Liz (New Zealand - temperate climate)
Have a look at this page www.gardenate.com/plant/Onion?zone=22
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11 May 20, Caswell Tlali (South Africa - Summer rainfall climate)
What will happen to my onion if I plant it in August in Lesotho (particularly along Caledon)? I am in Berea district in Lesotho. My fields are on the bank of Caledon River.
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Showing 31 - 40 of 88 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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