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 8°C and 30°C. (Show °F/in)
  • Space plants: 5 - 10 cm 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

08 Feb 13, Jase (Australia - cool/mountain climate)
Onions are immortal and can be re-planted after harvest. When cutting for food, chop <1.5 cm from the roots for re-planting. Water well and the onion will bulb into a few new plants. Separate the bulbs and you will have a new batch of onions.
17 Jan 13, solly (South Africa - Summer rainfall climate)
Need to plant brown onions now, is it the right time? How much water do onions need? How much fertiliser and when do i put it?
29 Jan 13, Conradt (South Africa - Summer rainfall climate)
I sow the onions in late January to early March, I prepare a patch in the vegetable garden for this. The stand where the onions will be transplanted to can be prepared in the mean time, If your soil is very heavy, sand can be worked in, as well as gracious amounts of organic fertilizer and ash (from your wood braai) This method give you time to ensure your bed is light and rich when your onions is ready to be transplanted around April. I use a clear plastic covering during coldest of winter months, just to keep the frost off. Hope this help.
06 Jan 13, liyungu mulikita (Canada - Zone 2b Sub-Arctic climate)
hi there,you people are doing a great job on lessons on how to grow onions.
26 Dec 12, Ronel (South Africa - Summer rainfall climate)
Looking for help, I am looking for seeds of the Egyptian Walking onion, also known as the Tree onion, Winter onion or Top onion. Please can anyone help.
23 Oct 12, jean Parsons (South Africa - Summer rainfall climate)
What is the best cultavar for picking and does it make a differance.
04 Aug 12, Kevin (Australia - cool/mountain climate)
No. The tops need to fall themselves ideally when they are ready. If the stem is thick and appears to be forming a seed head, then pull them out and eat first.
05 Jun 12, peggy (USA - Zone 5a climate)
for a better onion do you fold over the tops of the onions when they get tall
10 Mar 14, GJX (USA - Zone 5a climate)
yes, this causes the bulb to get bigger
20 Apr 12, (Australia - cool/mountain climate)
I must be very lucky! I ignored everything the onion pack said (like covering with seed raising mixture, etc) and planted the seeds right into the dirt. Rather than the seeds taking 21-28 days as the packet said, they came through in 10 and going really strong :) All the best :)
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