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

11 Aug 09, (Australia - temperate climate)
I have geown onions for sometime with very ittle success, why don't the bulbs swell?
27 Jul 09, Barb (Australia - sub-tropical climate)
Hi Mel, if you select the climate zone for your area in Australia, then the planting guide will tell you which months you can plant onions in your area.
29 Jun 09, Mel (Australia - cool/mountain climate)
i am interested in planting onions, does this chart shown about growing months occur to Australia?
23 Apr 09, Evelyn (Australia - cool/mountain climate)
Evelyn, I live in a cool mountain area with frosty winters. I sow onions successively from March through to August. I like to grow long keepers, Creamgold being my favourite as I have kept them for up to six months (ate them all by then so don't know how long they keep). I have also sown Ailsa Craig for the first time this year and would be interested to hear feedback from anyone who has grown that variety.
18 Apr 09, Gervaise (Australia - temperate climate)
where can i find onion sets for spring planting...not seed but the actual bulb...im in NSW...?
16 Mar 09, David (Australia - temperate climate)
Ferolyn: The black (sharp) bits in the "pom-pom" are seeds. Yes you will get onions off them if you plant them. No, once the Onion has flowered it is pretty useless as an onion. Evelyn: day length sets teh onions "growing' it's bulb. you need the onion plant to grow in height BEFORE it grows its bulb else you end up with "sort of" spring onions. In canberra with heavy frosts probably better to wait til mid winter before planting. Graeme: timing is the key. If you live near the bay then you should be good to plant mid-late april (depending on the variety) this will allow the plant to grow before it starts bulbing (longer days). I planted Hunter River Browns today (West Sydney) so I am expecting a harvest of HUGE onions Nov-Dec
15 Mar 09, Graeme (Australia - temperate climate)
I have grown onions from seed and bought seedlings for years, but they always "bolt" and run to seed. What is the secret to growing them successfully? I don't want to give up just yet, but I am getting frustrated. I live in Melbourne which I think is classed as temperate
15 Mar 09, Evelyn (Australia - cool/mountain climate)
I was wondering if it is too late to plant onions now in Canberra. I believe day length is the key but not sure which ones are which. Any assistance appreciated. PS. I have never grown onions before.
14 Mar 09, Ferolyn (Australia - temperate climate)
I found a forgotten red onion in my cupboard few months ago and it already has aboiut 3inches of shoot. I planted it. Now I have a tall stem of about almost 3feet with a pretty pompom flower on it. Would i still have onion out of it? It now has little pids on the pompom. I broke one of its pods out of curiosity and it has little black round bits inside... is that the seed? Would i get onions if i plant those seeds?
09 Jan 09, stewart (Australia - cool/mountain climate)
Discovered onions growing (planted by previous owner of property) so I dug some up (brilliant white). All sizes and some throwing new ones off the roots?Cut a larger one up to find only about 4 layers and then solid onion? What's the go? Is this about storing and then they develop the other layers? I've not grown them before so have no idea.
Showing 351 - 360 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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