Growing Onion

Allium cepa : Amaryllidaceae / the onion family

Jan F M A M J J A S O N Dec

(Best months for growing Onion in Canada - Zone 3a Temperate Short Summer regions)

  • S = Plant undercover in seed trays
  • T = Plant out (transplant) seedlings
  • 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 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 .
06 Oct 22, Melinda Schwab (USA - Zone 8a climate)
Absolutely! We do all the time! We always cut the onions we buy horizontally in half when cooking and carefully peel down to the middle chunks where you can see how many "dots" are gonna be onions next year. We have a big patch of sandy loose soil that has a lot of chicken manure and/or compost here or there that we plant all of them in. We plant them an inch or so under the soil (totally covered up is best but not too deep) and we do not break them apart first. They grow into BIG beautiful onions in a year or so if you give 'em a drink of water when its dry for weeks. AND they make seeds too! Good seeds if you let them dry all the way out! We love getting free food from cooking scraps... with a bit of pre-planning on slicing the onions right to begin with... Try replanting carrot tops if you want fresh seeds... the top 2" of a regular carrot grows into fluffy foliage and sends up nice fresh seed heads in late summer. Freebies are fun!
09 Jun 22, Michael Pellerin (Canada - Zone 5a Temperate Warm Summer climate)
I Live in Miramichi, NB Canada and looking to what growing zone I am in and what type of oignions grow better, short day, intermediate or long day , or what varieties are better for my zone Thank-you
17 Jun 22, Anonymous (Canada - Zone 4b Temperate Warm Summer climate)
Go to the blue tab above and work out which zone you are. Pick what variety you want to grow.
02 Jun 22, Rick Nuffer (USA - Zone 7a climate)
do walla walla onions grow well in Utah?
18 Apr 22, Graham Bower (Australia - temperate climate)
I have been growing butternut pumpkin and trombone zucchini in close proximity and saving seed for following season. I saved seed from each for this seasons planting. This year my produce appears to be a cross of thes two . Is this possible? Can these cross pollinate? The fruit has been huge and eats very much like a quality butternut.
21 Apr 22, Anonymous (Australia - temperate climate)
I believe they do cross pollinate.
Showing 11 - 20 of 327 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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