Growing Onion

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

(Best months for growing Onion in New Zealand - cool/mountain regions)

S = Plant undercover in seed trays T = Plant out (transplant) seedlings 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
  • Red 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

07 May 21, Pablo checkman (South Africa - Dry summer sub-tropical climate)
How many month it takes Africans best onion
10 May 21, (South Africa - Semi-arid climate)
Read the notes here, www.gardenate.com/plant/Onion?zone=22
02 May 21, Michele (New Zealand - cool/mountain climate)
I seem to have gotten white rot/fungus tha affects most onion varieties except spring onions- they will get it but very late on...does anyone know of a vigorous type of ordinary brown or red onion that might stave it off until I can harvest? Thanks.
10 May 21, Tony (New Zealand - temperate climate)
try spraying regularly with copper, also good for rust.
06 May 21, Anonymous (New Zealand - temperate climate)
Ring your local agricultural or agric company department about the fungus.
06 Apr 21, Duke Rick (USA - Zone 8b climate)
What is the best time to plant Maui onion seeds in my zone?
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.
25 Mar 21, Jean (Australia - temperate climate)
My onion bed is prepared with plenty of chook poo, and top soil containing sheep and cow manure..plus lime and water retaining dressing.. Are there any other element missing or anything l'm putting on that is not necessary.? Why do the onions have thick necks? Am I leaving the onions too long before harvesting when seed stalks appear? I would appreciate your advice. I live in Lake Clifton 6215 WA on sandy soil which we are building up with compost and manures , lime etc
26 Mar 21, Anonymous (Australia - sub-tropical climate)
Onions don't need really rich soil, as in heaps of nitrogen. They are a bulb and need Phosphate. With the sandy soil better to build it up with mulchy compost, it can have a bit of chicken/sheep/cow manure in the compost. Or at the end of your growing season add manures grass clipping leaves etc to your soil and turn it and water (rain hopefully) during your fallow time, If you do that over 3-4-5 months then you should have really good soil to start with. You may need to add some lime to balance the soil ph back to 6-7. If you have big thick leaves stalks that means too much nitrogen.
Showing 1 - 10 of 287 comments

Read the notes here, www.gardenate.com/plant/Onion?zone=22

- Anonymous

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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. GardenGrow 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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