Growing Onion

Allium cepa : Amaryllidaceae / the onion family

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

(Best months for growing Onion in South Africa - Summer rainfall 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 8°C and 30°C. (Show °F/in)
  • Space plants: 5 - 10 cm 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

18 Dec 20, Sydney Thama (South Africa - Summer rainfall climate)
hello it is safe to plant onion around July and August?
21 Dec 20, Anon (South Africa - Summer rainfall climate)
Go the onion page and check when to plant onions in your climate zone, or google and research about growing onions.
13 Oct 20, Kelly (South Africa - Summer rainfall climate)
Hi there, I planted white onions in May, they have not yet yellowed and the stalks have not fallen over- we're having a lot of rain fall early on and I am afraid they will rot if I leave them in the ground while it rains so much. Can I harvest them before they have yellowed or will they still mature correctly despite the rain? Any tips or advice would be much appreciated Thanks
16 Oct 20, (South Africa - Summer rainfall climate)
It says plant seed Feb Mar and you planted May, that is the problem. Check to see how big they are, if a good size pull out. You be the judge, keep an eye on them, if they look like going rotten out they come.
13 Oct 20, Liesl Mittan (South Africa - Summer rainfall climate)
We planted onions late in march , they are ready and some are flowering .They should dry in the ground , but we are having rain. What do I do . Take them out and dry them hanging or leave in the ground and hope for hot weather . Thanks
19 Oct 20, (South Africa - Summer rainfall climate)
Pull them out.
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.
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.
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
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.
Showing 21 - 30 of 83 comments

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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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