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Growing Onion

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 = Plant in the garden.

  • 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 in same bed): Lemon Balm, Borage, Carrots, Beets, Silverbeet, Lettuce, Amaranth
  • Avoid growing in same bed: Peas, Beans
  • Red onion
    Red onion
  • Young brown onion
    Young brown onion

Onions come in a range of colours and shapes and sizes. Brown :- strong flavour and pungent. Usually good keepers for storage. White :- milder but still flavoursome. Keep fairly well. Red :- Mild, suitable to use raw in salads and sandwiches. The seedlings should be allowed to gain a bit of strength before planting out - usually 4 to 6 weeks will be enough. When they are big enough to handle, you can plant out. They start off looking like blades of grass.

They don't have to be in a greenhouse (though that would be ideal), any sheltered spot will do. The idea is to guard against rapid changes of temperature, especially at night.

Onions can be bought as young plants (sets or seedlings) from garden shops/nurseries to plant straight into garden beds. Choose your variety according to your climate and the time of year as some onions will grow better in the cooler months .

Onion bulbs should sit on the surface of the soil. Do not cover. They will take six to eight months to mature. Onions are ready when the tops start to dry and fall over. Pull them and leave to dry for a few days. Store in a cool, dry airy place. Use a net bag or make a string by weaving the tops together.

Culinary hints - cooking and eating Onion

Brown onions roasted whole with other vegetables are delicious.
Red onions add colour to salads or stir-fry.

Your comments and tips

18 Mar 17, irene (South Africa - Semi-arid climate)
every i plant onion they dont come out what can i do plss help or tips.
21 Mar 17, John (Australia - temperate climate)
Onions are generally fairly easy to germinate. They need to be planted about 3 times their diameter with soil. A good way to do this is to sprinkle the seed over a small area that has been broken up and is very fine then cover with some more fine soil. Keep the soil damp but not wet. When the seedlings emerge they will be very fine like a needle. keep them damp but not wet as they may get fungus problems. A spot that gets some sunshine and a bit of airflow is good. They will take about 4-6 weeks before they are ready to transplant into rows in the garden. They will take about 6 months to be ready to harvest and store (when the tops flop over and start to dry). I hope this helps. Don't hesitate to ask questions, we are here to help.
25 Feb 17, Eric ryan (Australia - temperate climate)
Can I grow onion in Hervey bay qld the sweet variety preferably
26 Feb 17, John (Australia - temperate climate)
Onions like a cooler climate but you could try Creamgold (Pukekohe) in late March or April for late spring/early summer harvest. As an alternative try shallots or potato onions. Onions don't like too much manure/fertiliser and need an open sunny spot with good airflow to avoid mildew problems. All the best.
20 Feb 17, michael kearns (Australia - temperate climate)
Which type of onion is better. brown or yellow
20 Feb 17, John (Australia - temperate climate)
They are both good depending on what your intended use is. Brown onions are often smaller and more pungent but Creamgold (Pukekoe), the creamy yellow one is larger with a smoother flavour. I suppose you could say Creamgold is the ideal BBQ onion as it onlly needs light frying. It is entirely a matter of personal preference. Trust this helps.
01 Feb 17, Grace (Australia - temperate climate)
I'm looking at onions. Temperate area. Cohuna vic. What isnthe difference between the "transplant seedlings" and "plant in garden"? Hmmm. Or does the "plant in garden" mean I can plant seed straight into the garden instead of growing them now in seed trays?
04 Feb 17, John (Australia - temperate climate)
Any seeds planted directly into the garden will do better than transplants because they don't get any transplant shock. Having said that it is not easy to sow onion seed far enough apart to achieve this without thinning. Seed sown directly into the ground in friable soil will do a lot better than tray grown seedlings generally because moisture is easier to keep more consistent. these can then be transplanted. Trust this helps and is not too confusing.
29 Jan 17, Anthony (Australia - temperate climate)
I am keen on growing brown onions at home in Sydney..i have been reading up on onions and found that there are long day short day and intermediate day varieties...which verity best suits Sydney this winter and even next summer...Also whats the best variety of onion that best suits Sydney....Im near Parramatta... Also where would the best place to get seeds for this variety of onion... Thankyou....
04 Feb 17, John (Australia - temperate climate)
We are south of Sydney but I think it would be about the same. Check the seed packets or catalogue when purchasing. Feb-Mar - Early White Barletta, Erly Flat White (salad onion) Apr-May - Golden Globe, Hunter River White, Hunter River Brown, Gladalan Brown Apr-Jul - Odourless, Calred (Californian Red), Pearl Pickler May-Jul - White Spanish, Australian Brown, Brown Spanish Jun-Jul - Pukekohe (Creamgold) Jul-Sep - Ailsa Craig, White Spanish, All Year - White Lisbon, Long White Bunching (spring onion) I am indebted to Norman de Vaus for this information. He has a seed company called New Gippsland Seed Farm which you should be able to find on the internet. Trust this helps.
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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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