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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20 Jul 20, Mike (New Zealand - temperate climate)
I took a look at the I'iotoi onion on google, the photo of them is the closest /the same to what I grow. I have always called them shallots and so did my mother. I/we have been growing them for nearly 60 years. Keep bulbs from one year to the next to replant. The only problem is I live in Australia, near Bundaberg Qld. A lot of people call different things shallots. If you are unable to obtain any in NZ you could ring your agric department and see if I could send some to you. Ring up some of the seed selling companies in NZ to see if they have them.
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16 Aug 20, Elaine (New Zealand - cool/mountain climate)
Mike thanks for your reply. The shallots you are talking about like the Iitoi in America you ave grown in Bundaberg for 60 years are exactly the same ones my Mum grew. I came from Brisbane Qld where she grew them for probably about the same length of time too. They are unique as they don't seed. I'm not sure Customs would let them into NZ as I know they are strict on fruit. I would love to get some but not sure how.
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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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22 May 20, Anonymous (South Africa - Summer rainfall climate)
Gardenate suggests you plant Feb to April. Try planting it in August and it probably won't even germinate. Most plants have a defined time of the year to grow in a particular climate zone.
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12 May 20, Anon (South Africa - Semi-arid climate)
Check the top of the page .
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08 Apr 20, Harpreet Kaur (New Zealand - cool/mountain climate)
If you sow seeds of red onion indoor in April and wait till it can be transplanted outside..say in June.. Can it stay in the ground in cold winters harmlessly..n mature in summers to come around Christmas? Or will it die in cold weather buried in soil ?
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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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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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