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

25 Feb 21, Brad (Australia - sub-tropical climate)
Depends on the variety of brown onion mate, the more pungent ones will store longer but they are more suitable to cooler areas. I'm sub-tropical too i'm from brisbane and I do a variety call "Texas early granno" I pulled about 70 to 80 out last year and none went bad. The trick is to harvest them when you need them. Green Harvest is a great site where I get most of my seeds from they are situated in south-east Qld and they have a lot of info of different varieties and the climates they are best suited for. Hope that helped Brett. -Brad
16 Feb 21, Judith c Greenleaf (USA - Zone 9b climate)
Can I plant onion sets in February or march? what sweet onion varieties do you suggest for No. Ca. marine zone 9B? Thank you.
17 Feb 21, Anonymous (USA - Zone 9b climate)
Consult the planting guide calendar and the footnote at the bottom of the page. If it says plant April and you plant Feb, the seeds/sets probably won't germinate/survive . There are reasons why it says to wait until April but take local conditions into considerations.
12 Aug 21, Carol Rose (USA - Zone 9b climate)
I found Dixondale Farms to be a great help. I ordered my onion slips form them. I had never ordered onion slips before so I was a little nervous about the process. I wasn't able to plant them when they arrived but I cared for them as per instructions and only lost a few before I could get them into my newly made raised beds. I planted sometime in early June I think and they are about 3 weeks or so form being ready. I live on the Central Coast of California and these onions look great. As a pretty new organic gardener I love to share my successes. Ck out Hollis and Nancy's homestead on YouTube. It is so helpful!!
12 Feb 21, Rosie (Canada - Zone 5b Temperate Warm Summer climate)
How do you care for onion plants: weeding, cutting back,spooning,fertilizing,watering?
02 Mar 21, (Canada - Zone 5a Temperate Warm Summer climate)
Start with good loose soil that has had some fertiliser, compost, manure put in it, don't over do it though. Water every day when small and then each 2 days when half grown. Keep weeded.
03 Feb 21, Sky Kell (USA - Zone 7b climate)
Perennial onion that multiplies for 7b zone
18 Dec 20, Sydney Thama (South Africa - Summer rainfall climate)
hello it is safe to plant onion around July and August?
21 Dec 20, Anon (South Africa - Summer rainfall climate)
Go the onion page and check when to plant onions in your climate zone, or google and research about growing onions.
13 Oct 20, Kelly (South Africa - Summer rainfall climate)
Hi there, I planted white onions in May, they have not yet yellowed and the stalks have not fallen over- we're having a lot of rain fall early on and I am afraid they will rot if I leave them in the ground while it rains so much. Can I harvest them before they have yellowed or will they still mature correctly despite the rain? Any tips or advice would be much appreciated Thanks
Showing 101 - 110 of 371 comments

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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