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 Nov 16, Atholl Selkirk (South Africa - Summer rainfall climate)
Where can I purchase onion sets in South Africa, Gauteng?
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15 Nov 16, Bob (Australia - temperate climate)
I planted white onions seedlings (variety unknown) in mid-June with the usual expectation that they would be ready for harvest in early December; when the tops usually start to dry out. This year about 50% of the plants have started to produce flower buds in early November. I suspect that if I allow them to flower; the quality and storage-life of the onions will be reduced. Should I harvest them before the first flowers blossom? Regards Bob.
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18 Nov 16, John (Australia - temperate climate)
Onions are biennial, that is they grow and die down in he first year then regrow and flower/seed in the second year. If seedlings of biennials are stressed in the punnets before they are planted or if the variety is not suitable for planting at the time of the year the plants may be triggered to flower and set seed. If you leave them they will increase like daffodil bulbs.
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25 Oct 16, Trish (Australia - temperate climate)
Hi - I want to use the seed from my onions to plant for the next round. How should I do this?
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27 Oct 16, Tempest (Australia - temperate climate)
Leave your best/biggest onion(s) to go to seed. It may take a while, but it's worth it to have all the extra seed. My friend did this but wasn't able to harvest the seed when it was ready - she now has lots of onions popping up around the original onion. Best excuse for less effort! ;)
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17 Oct 16, nompumelelo (South Africa - Semi-arid climate)
what is the best growing season for onions in KwaZulu Natal, South africa e.g feb-march? and ehat are the heat unit requirements
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10 Jul 16, Cassie (Australia - cool/mountain climate)
So why did my onions grow well then split and sprout? They have no intention of having their tops die back. Previously I've had them go to seed and clearly avoid the whole 'tops dying back' thing too. I sow seed in late winter and plant out the seedlings in early spring. What am I doing wrong?
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08 Jul 16, Andrew (South Africa - Summer rainfall climate)
is it possible for me to grow onion in summer and which variety of onion can strive better
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18 Jun 16, Christine (Australia - tropical climate)
I have onions shooting in the vegie bin. My son said when I plant them I have to put the new growth above the soil, but I though this was the root. Which way do I plant them please?
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01 Jul 16, Barb (Australia - temperate climate)
Your son is right - the green shoots are the stems/leaves starting to grow. So plant these uppermost. I find the ones that I grow from shooting onions may not bulb up properly. but they make great spring onions, and if left will divide so you'll have a little patch of spring onions.
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two questions. Which variety of onions and garlic are best for growth in Puerto Rico. were can I buy them and expect to get them to Puerto Rico. Many say they are not to be shipped to Puerto Rico(price for living in the colony). Thanks, C.Foy

- Clifford Foy

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