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jal_ut
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Location: Northern Utah Zone 5

Re: Growing onion from Seed

Onions are day length sensitive and bulb when the days are of the right length. They are also a cool weather plant so need to be planted early to grow while it is cool. In the South onions can likely be planted in December and they will be old enough to bulb while the days are still short. Hence Short Day Onions for the south. In Northern latitudes planting time is later when the days are longer, hence Long Day Onions for the North.

If I plant seed here the best I can hope for are some the size of golf balls. (or plenty of green onions) If I plant sets or small plants, I can get some nice large bulbs.

Some types are said to be day neutral.
Gardening at 5000 feet elevation, zone 4/5 Northern Utah, Frost free from May 25 to September 8 +/-

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rainbowgardener
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Re: Growing onion from Seed

yes, for me here right on the border between north and south, day neutral onions seem to work best for me. Candy is one I have had success with.
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digitS'
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Re: Growing onion from Seed

Candy did okay for me (once I stopped trying to grow them in partial shade :roll: ). But, I've grown lots of varieties of long-day and intermediates onions with good success here at about 48° North.

short day -- 11 to 13 hours of daylight
intermediate -- 13 to 14 hours of daylight
long day -- 14 hours or more of daylight, to form bulbs

Here is what Oregon State University has to say on short day onions in the north: "If you grow short-day onions at northern latitudes such as Oregon, when the days reach short-day onions' critical photoperiod (11-13 hours of daylight) it is only March. The soil is still cold and the onion plant will still be tiny, forming only a tiny bulb." link

Okay, OSU is at about 45° North latitude. That line runs through southern Montana, central Wisconsin, southern Ontario, Vermont ... like that :).

I actually tried to grow Granex here once. Hey! I don't like to be left out! If folks were enjoying that onion in Texas and Vidalia Georgia ... I could eat them ... as anyone might ... eat a golf ball sized onion. I don't think some even made it to that size, rushing to form bulbs!

:) Steve
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imafan26
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Location: hawaii, zone 12a 587 ft elev.

Re: Growing onion from Seed

I planted my onions and garlic in September. The sprinkler timer died and so did most of the onions. A few did survive. I think all the garlic is gone. I won't be able to plant more until the fall. It is too late for me to plant anymore from seed. Good luck with yours.
Happy gardening in Hawaii. Gardens are where people grow.

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rainbowgardener
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Re: Growing onion from Seed

It probably is too late for garlic and for onions from seeds, but you could probably still pop onion sets in...
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imafan26
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Re: Growing onion from Seed

There actually are no onion sets sold here. Everyone who plants onions plant them from seeds in the fall. The big box stores will bring in onions but they are usually not the ones suitable for this climate. They probably send everything out to every store in the country without really paying attention to regional considerations. I can only grow short day onions. If I start them now, they won't have enough top growth to bulb up.

I planted them out of season when I did not know better, and garlic too, I ended up with no onion bulbs and garlic that was smaller than what I started with. It was elephant garlic-- I should have ate them instead. I didn't know I could not grow elephant garlic in Hawaii.
Happy gardening in Hawaii. Gardens are where people grow.

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applestar
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Location: Zone 6, NJ (3/M)4/E ~ 10/M

Re: Growing onion from Seed

Couldn't you grow day neutral varieties from seeds more or less year round? I guess no sets because of the extra cost and paperwork involved in live plant shipping to Hawaii?

Onions are said to be shallow rooted and that's true but the initially seedlings grow surprisingly deep roots and I found shallow-- 1" or less depth seed starting containers were too shallow.

Mine are starting to sprout now :()
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