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

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09 Feb 15, Clifford Foy (USA - Zone 12b climate)
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
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28 Nov 20, Sandra Garcia (USA - Zone 10b climate)
Try Baker Creek; I get all my seeds there, I also use Trade Winds Fruit, Baker Creek has videos and they tell you the temperature that the plant can grow in, but you need to research each seed type to see what weather it grows well in. Read the reviews for the plants to see what others say about it. You can definitely grow everything all year round! Good luck
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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
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10 Mar 14, GJX (USA - Zone 5a climate)
yes, this causes the bulb to get bigger
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Showing 41 - 44 of 44 comments
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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?

- Ferolyn

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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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