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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30 Mar 14, (South Africa - Summer rainfall climate)
Hi, Where can I buy onion sets / bulbs for home growing ?
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22 Feb 14, Ali (Australia - temperate climate)
I am still drying out on onions I have taken it the top the the onion(where all the seeds are) but they are still green. What do I do? When do I plant them? Would they turn out okay!!?
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13 Feb 14, Hlumelo Somniso (South Africa - Summer rainfall climate)
i am at Alice (eastern cape ) what is the right time to plant australian brown.
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10 Feb 14, kathleen harris (Australia - temperate climate)
Can you recommend a variety of onion that I can grow for pickling. The pickling onions in the shops are too big and not nearly crisp enough.
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07 May 14, Ted (Australia - temperate climate)
Kathleen we plant out cream gold for pickling have done it for years. Plant them close together rather thickly and harvest in summer. They can sit around for ages if needed before you pickle them. Very crisp.
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06 Nov 13, doug Dewar (Australia - arid climate)
i have planted onions and spring onions over the top of pea mulch and a lot of seeds have germinated, i have been pulling them out as they come up and finally they have all gone.Should i use sulphate of potash to balance out the high level of nitrogen in the soil as i do not want to lose them because they take so long to grow,hoping you can help me,thanks doug dewar.
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07 May 14, Travis Edwards (Australia - temperate climate)
If anything you will find that the decaying pea straw will be sucking nitrogen out of the soil while it is decaying once it has composted down well it will be nitrogen rich however. lime, and gypsum, would be a good additive as the decay process tends to be acid and onions prefer a slightly alkaline soil. (lime and gypsum will help neutralise the acidity.)
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14 Nov 13, Norma (Australia - temperate climate)
I planted my red onions, in a patch where my beans were, they took twice as long to grow than my brown onions planted nearby in virgin soil, brown onions are almost the size of a Pomello, red onions are still coming on. Onions and pulses, beans and Peas) definitely are enemies
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23 Oct 13, Anne (Australia - temperate climate)
what to do? my onions have developed flower stalks, it is mid-spring
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27 Oct 13, Ferran (Australia - sub-tropical climate)
Are the onions ready to harvest? Could you harvest them? preventative ways to stop them putting their energy in to flowering are: cutting off the flower stalks, shading them, keeping them moist. Good luck!
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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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