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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08 Feb 08, Bryan (Unknown climate)
Onions can be successfully planted as seedlings.Grow in trays transplant at about 15cm.Before transplanting trim tops and roots by about one third, dig shallow depression, lay plants with roots only in depression and cover roots with soil. Important to select correct onions for time of year(see packet)
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04 Feb 08, Liz (Unknown climate)
Onions can be raised in seed trays or punnets and transplanted when about 10-15cm tall. They should be planted with just the roots covered. If sown direct, the emerging plants may need thinning. I have been successful with both methods for brown and red onions and with spring onions from seedlings.
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01 Feb 08, Matt (Unknown climate)
Hi there Im a development Horticulturalist with Fairfield city council, I just wanted to find out what types of onion are transplanted from seedling. The reson i ask is i have only ever heard of direct sowing of onion seed and transplanting is very unsucessfull (especially in your common spanish, white and brown varieties).
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My home garden is NS and a men's shed gardens I had were NS. I'm now in a new garden set up that is EW. I have wondered about the difference. My thoughts are with the plantings NS, ALL plants have sun on them all the day whatever hours that is. The sun from the E in the morning and W in the afternoon. With the EW some plants might be shaded by other plants during the day. Different beds could be different soil fertility, hrs of sunlight, watering etc. Generally when soil nutrient and/or water are not sufficient the plant will flower and set seed to be able to reproduce in the future.

- anon

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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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