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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26 Apr 23, Erin (Canada - Zone 5b Temperate Warm Summer climate)
You need a long day onion, you can start seed ahead of time indoors, do not save seed packets, they're only good for a year.
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19 Apr 23, (Canada - Zone 3a Temperate Short Summer climate)
Read the planting guide at the top of the page and plant the variety you want to eat.
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14 Apr 23, CJ (Canada - Zone 5b Temperate Warm Summer climate)
CAN I GROW IN CONTAINERS AS I LIVE IN AN APARTMENT
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12 Apr 23, marco (Australia - sub-tropical climate)
hi i live on the gold coast Queensland . i have planted my onion 2 weeks ago in the cloudy times .ok .then we hit harsh sun times .i had to cover and they are ok growing well .if u just leave them in the sun they fry .....my second batch i lost maybe half my crop ...
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05 Mar 23, Lori (Canada - zone 4a Temperate Warm Summer climate)
What onions grow best in zone 4a?
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01 Mar 23, Susan (USA - Zone 6b climate)
Can I direct sow intermediate onion seeds in fall in a raised garden bed covered with leaves and over winter them. Zone 6b
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29 Jan 23, Gladis (USA - Zone 10a climate)
What variety grows best in zone 10a (Southern California)?
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07 Jan 24, Lisa (USA - Zone 10a climate)
Any Short Day onions. Google "Short Day Onions". I also live in Southern California and just received my onions sets from Dixondale Farms.
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29 Jan 23, Ron Holt (USA - Zone 7b climate)
I would like to grow onions (sets) in my garden this Feb. 23 to be harvested as mature onions in about 6 months. I would prefer sweet onions. Can you suggest a a particular type ? Do I need to buy heated onions? Thanks, Ron
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19 Jan 23, Sharon Burke (USA - Zone 7b climate)
I took a kitchen scrap from a yellow onion and now I have roots what kind of soil should I plant this in for indoor in January please and thank you
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Showing 21 - 30 of 360 comments
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Onions are generally fairly easy to germinate. They need to be planted about 3 times their diameter with soil. A good way to do this is to sprinkle the seed over a small area that has been broken up and is very fine then cover with some more fine soil. Keep the soil damp but not wet. When the seedlings emerge they will be very fine like a needle. keep them damp but not wet as they may get fungus problems. A spot that gets some sunshine and a bit of airflow is good. They will take about 4-6 weeks before they are ready to transplant into rows in the garden. They will take about 6 months to be ready to harvest and store (when the tops flop over and start to dry). I hope this helps. Don't hesitate to ask questions, we are here to help.

- John

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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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