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

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!!
28 Feb 21, Barbara Esparza (USA - Zone 9b climate)
Are there any onion sets that I can plant in Texas zone 9b that are more heat resistant?
02 Mar 21, Anonymous (Australia - sub-tropical climate)
Plants generally have a temperature range that they grow in. That is why most crops are seasonal in a district. Try planting out of that range and you could fail.
02 Apr 21, Debbie h. (USA - Zone 9b climate)
Can you plant onions that already have a green stem coming from it? Like ones in fridge if not used fast enough .
08 Apr 21, Anon (USA - Zone 4b climate)
Put the question into google and it will explain how to do it.
22 Jun 21, Jayne Matzkin (USA - Zone 9b climate)
I've done it. You take the outside layers off until you reach the layers the green stem is attached to and plug it in your garden. They become a bigger version of themselves. I see this a way of not wasting that onion and tossing it.
07 Oct 22, Janelle (USA - Zone 10a climate)
Yes, I just did exactly that this summer. Instructions on previous reply are correct.
06 Apr 21, Duke Rick (USA - Zone 8b climate)
What is the best time to plant Maui onion seeds in my zone?
05 Jan 22, don (USA - Zone 10b climate)
when you are on this page - just above the title
02 Jun 22, Rick Nuffer (USA - Zone 7a climate)
do walla walla onions grow well in Utah?
Showing 11 - 20 of 39 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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