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

29 Sep 22, (Australia - tropical climate)
Try planting at the begining of your driest part of the year.
24 Sep 22, digna carwell (USA - Zone 10a climate)
Hello I lived in 10A zone I would like to know when is the best time to grow , onions , garlic, carrots and mist vegetables? Thank you in advance for your response.
03 Oct 22, (USA - Zone 4b climate)
Check the planting guide for each crop.
07 Sep 22, Don Cropper (South Africa - Summer rainfall climate)
I am growing Australian Browns which I grew inside green house and planted out.They are making flower stems but the onions aren't ready to pull out yet.Can I leave the flowers to grow or must I cut them off.
13 Sep 22, (South Africa - Summer rainfall climate)
Sounds like your soil wasn't fertile enough to produce an onion bulb. The plant is going to seed already.
23 Aug 22, Adam Kulka (Australia - temperate climate)
Could you please advice why always my onion growing seeds heads, I try to grow from seeds or from last year young ones but no luck to have nice bulb in end of the growing season, I'm in Suthern Highlands NSW, thank you
29 Aug 22, (Australia - sub-tropical climate)
Do you plant the right time and is your soil fertile. Plants will go to seed if nutrient runs out. Regular watering also.
10 Aug 22, vivian gibson (USA - Zone 9b climate)
I have texas grano onions to make set. blue lake pole beans, purple hull peas, tomato(transplant),Bell pepper (Trans plants) when do I plant? putting them in my big pots these are all going into large pots.
01 Aug 22, Caridad Pupo (USA - Zone 8b climate)
Id like to grow some granex onions like the Texas Grano. Can I sow the seeds now in seed trays and plant them outside n September? Do the onions become dormant when the weather gets cold?
15 Jul 22, carmen rodriguez (USA - Zone 8b climate)
can i grow onions from bought from store ? i cut bottom of onions put in water as soon as it starts growing roots i plant them . when should i plant them and i have not been successful im in zone b please help me .
Showing 51 - 60 of 374 comments

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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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