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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07 May 21, Pablo checkman (South Africa - Dry summer sub-tropical climate)
How many month it takes Africans best onion
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10 May 21, (South Africa - Semi-arid climate)
Read the notes here, www.gardenate.com/plant/Onion?zone=22
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02 May 21, Michele (New Zealand - cool/mountain climate)
I seem to have gotten white rot/fungus tha affects most onion varieties except spring onions- they will get it but very late on...does anyone know of a vigorous type of ordinary brown or red onion that might stave it off until I can harvest? Thanks.
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10 May 21, Tony (New Zealand - temperate climate)
try spraying regularly with copper, also good for rust.
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06 May 21, Anonymous (New Zealand - temperate climate)
Ring your local agricultural or agric company department about the fungus.
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06 Apr 21, Duke Rick (USA - Zone 8b climate)
What is the best time to plant Maui onion seeds in my zone?
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05 Jan 22, don (USA - Zone 10b climate)
when you are on this page - just above the title
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02 Apr 21, Debbie h. (USA - Zone 9b climate)
Can you plant onions that already have a green stem coming from it? Like ones in fridge if not used fast enough .
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22 Jun 21, Jayne Matzkin (USA - Zone 9b climate)
I've done it. You take the outside layers off until you reach the layers the green stem is attached to and plug it in your garden. They become a bigger version of themselves. I see this a way of not wasting that onion and tossing it.
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07 Oct 22, Janelle (USA - Zone 10a climate)
Yes, I just did exactly that this summer. Instructions on previous reply are correct.
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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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