Growing Onion

Allium cepa : Amaryllidaceae / the onion family

Jan F M A M J J A S O N Dec
      S                
          T T          

(Best months for growing Onion in Australia - tropical regions)

  • S = Plant undercover in seed trays
  • T = Plant out (transplant) seedlings
  • 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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24 Oct 18, Michael Jones (Australia - temperate climate)
when do i plant cipollini onion seeds in west Australia
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25 Oct 18, Mike (Australia - sub-tropical climate)
Read the guide here. Plant first half of the year - probably after Feb - summer probably too hot.
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18 Oct 18, Malcolm Langley (Australia - sub-tropical climate)
I planted onions last season and thined out where necessary and had a reasonable crop.this season l did it a bit differently. I planted the seeds into pots and then replanted into the ground so that I didn't waste any by thinning out. The seeds used were the from the same suppliers and were brown onions as before. This season they are growing well but most of them have very thick stems and seed pods are formed. The onionbulb in lots of instances is not developing .am l doing something wrong? Mal.
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23 Oct 18, Mike (Australia - temperate climate)
I had this problem this year. First time I had grown onions. I put it down to too rich a soil. Maybe less N applied. And probably back off the watering a bit when they have grown for say 4 mths.
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06 Oct 18, Wayne (Australia - temperate climate)
Onion Red Odourless: Planted sixty seedlings in April which have been growing well but are now going to flower and bulbs have not formed. (Adelaide Hills)
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07 Oct 18, Mike (Australia - sub-tropical climate)
I grew onions for the first time this year. Mixed success. White ones. Some formed bulbs some didn't - good health plants - probably too much N. Onions can take 6-8 mths to grow.
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12 Mar 18, Albert (Australia - temperate climate)
When do l plant a giant decorative allium and how deep.? any other advice would be appreciated.
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13 Mar 18, Mike (Australia - tropical climate)
Type into google
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17 Jan 18, Joe Branco (Australia - temperate climate)
Why are brown and white onions sown at different times
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27 Nov 17, John (Australia - temperate climate)
Hello and thanks for your time I would like to grow red onions i live in the wrstarn suburbs of Adelaide when do I plant seed thank you .
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Showing 51 - 60 of 193 comments
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(FROM THE NET) Manganese and zinc deficiencies are the most common ONION problem that causes tops to prematurely bend over OR become disfigured....Tops falling over prior to the bulb reaching maturity can result in decreased yields Young plants are particularly sensitive to Zn deficiency..... Problems are more common on high pH or calcareous soils or during cold, wet weather.... I suggested adding poultry manure (chicken manure) -- poultry manure tends to be high in Zinc, in a well balanced way. .Zinc also exits naturally in rocks. The amount of zinc present in the soil depends on the parent materials of that soil. Sandy and highly leached acid soils generally have low plant available zinc. Cool soil temperatures in early spring can intensify the need for zinc. Root growth is also stunted by cool temperatures and reduces the plant’s ability to find new sources of zinc in the soil profile. Also note: -onions and other alliums need more phosphorus and potassium than most other vegetables. They also need more copper, manganese, zinc, and molybdenum. Also please be aware that : There is a known relationship between phosphorus and zinc in the soil. Excessive application of phosphate fertilizers can caused zinc deficiencies. A phosphorus-induced zinc deficiency is a concern and may occur only if very high rates of phosphate fertilizer (more than 200 lb P2O5/acre) are used and the soil has zinc levels is in the range between Low and Very Low.

- Celeste Archer

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