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Super Green Thumb
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Location: TN. 50 years of gardening experience.

How to grow onions from seeds?

Last year I planted 3 types of onions from seeds and none grew?

I am getting my garden ready for winter I plan to have a 30 ft row of onions.

What is the best way to grow onions from seeds?

Super Green Thumb
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Location: New Orleans

I prefer to plant onion sets instead of seeds. I get the sets from a local nursery and usually split the variety down the middle by getting equal sets in the yellow onion and red variety. In the south and grown over the fall/winter months it is best to get short-day varieties that only require 12-14 hours of sunlight a day and I usually put them in the garden in October.

Last year I had tons of growth and used a lot of the green stalks for cooking as they were no different than green onions, only much bigger. However, my bulbs didn't get as big as they have in the past for some reason. In previous years I had some onions get to be the size of softballs, with most of them being the size of a tennis ball or regular baseball.

I will put them in the garden this year to see how things go, and hope for better results this year.

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Location: Gardening in western U.P. of MI. 46+ N. lat. elev 1540. zone 3; state bird: mosquito

I never had nice winter onions til I started growing them from seed indoors in a flat. 6 to 8 weeks in there then set outdoors late spring. But in your area, I don't know.

I read in an old Organic Gardening a few months ago, that in some climates, if you plant onions out in fall to get a harvest the next year, they sometimes are fooled into thinking they are in their second year of growth and then like to go to seed. Have searched for that article again but can't find it.

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Location: Northern California; Hardiness Zone 10a, Climate zone: 17

You know, onions from seed seem to me to be really fickle - sometimes none come up, and sometimes germination is really high. This, regardless of type of onion. I probably should spend more time trying to figure out why, but I'm usually too impatient to get my seedlings started and my garden planted. :roll:

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Onion/allium seeds are one of those that lose viability pretty quickly I believe. 2-3 years, maybe?

If you are sowing them this fall, I posted this last year in response to another thread. How cold does it get in winter where you are?

Of course it gets much colder here -- I tried Walla Walla and White Wing which is supposed to be "similar to Candy" and Walla Walla survives here in protected bed but White Wing was pretty much wiped out over the winter.

Subject: Trying Onion Sets.. in my area?
applestar wrote:What you would need to watch out for is killing freeze that could wipe out bulb onions. According this, Walla Walla variety and most potato/multiplier onions are hardiest and can survive down to 5°F (-15°C): ... wling-2013

Besides Walla Walla which is the only one I had heard about, Candy and Bridger are also killing freeze hardy varieties, according to this article:

Plant onions for overwintering now - The Washington Post ... story.html

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Super Green Thumb
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Location: ID/WA! border

Onions from seed is my most common way for growing a crop but I do buy some sets every spring for early scallions.

Seed goes in flats of soil mix in the greenhouse about 1 February. Shortly after the time that seedlings started in the house are moved into the greenhouse (15 March), the onions can begin spending time outdoors. I will still be protecting them from freezing.

Sowing Walla Walla onion seed in the open garden proved to be successful only about once every 3 or 4 times. A late August sowing date resulted in a good stand of seedlings going into winter. But, too many of the plants bolted to seed in early summer instead of forming bulbs. An explanation from an onion farm was that too cold of winter temperatures was the problem. Gave up trying.

Those were sub-zero winters, Gary. Onions in your warmer winter location should not be prompted to bolt in that way.


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Super Green Thumb
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Location: Northern Utah Zone 5

Quote: "What is the best way to grow onions from seeds?"

I don't know about growing onions there it TN. I do know onions are a cool weather plant. Here I plant seed early Spring as soon as the snow is off and I can get on the plot. I just plant the seed in a row and cover shallow, about half an inch. They come up and make a lot of green onions. If let go full season, they may get little one inch bulbs. If I want a big onion I need to plant onion sets in the Spring.

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Super Green Thumb
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Location: Northern Utah Zone 5

Also, there are short day onions and long day onions. It seems the onions bulb up when the days are of a certain length. It has been said short day onions for the South and long day onions for the North. So I suggest getting some short day seeds and plant them in early February. Good luck.

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Location: Hanover, Ontario

I have always used 'set's to plant my onions in the early spring (April/May here). I was reading that onions grown from seed were better quality. This year I ordered some seeds and started them around Feb/March in a sheltered, but cool area. Transplanted and they didn't take. Bought started sprouts and they didn't take. Round 3 planted end of May, only about 50% are currently growing, but they look smaller than any I have grown from sets. Have to say my experience hasn't been great with seeds...I like to grow and store all my own onions for the year and I just won't have nearly enough from this season!

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