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Greener Thumb
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Location: Monterey, CA.

When to plant Onion seeds?

I have seeds for Crimson Forest Bunching Onions, Red Bottle Onions, and Yellow Borettana (this one is a long day variety). I also have seeds to a few different Leek varieties. I don't use Leeks much but like to plant a few here and there and use them if I need them. When is the best time to start the seeds, and would I be ok growing the long day variety down here? How long will it take to have harvestable bulbs?

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Super Green Thumb
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I don't really know a lot about onions and all the different types. But onions are slow from seed. I would think in your climate you would want to be planting onion seed now. I often plant onion seed in the fall to overwinter and then be harvested the following summer.
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Joined: Tue Nov 02, 2010 12:00 pm
Location: Chicago area

When to plant Onion seeds?

Hey Punk Rotten. Ken here in the Chicago area. In your area the seeds should
Be planted in fall to early winter. Your bunching and red bottle onions should
work out fine. The long day variety will have trouble bulbing up. It needs 14-16
hours of daylight to produce bulbs. Grow them anyway for scallions or green onions.
Let us know how they grow.
Ken here with The Home Depot in the Chicago area

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Super Green Thumb
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Location: Wentzville, MO (Just West oF St. Louis) Zone 5B

Normally a long time ago. You can try seeds but get them in NOW!

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Super Green Thumb
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Location: Northern Utah Zone 5

Ok, first remember I am in zone 5 at 5000 feet elevation. A whole lot different climate than you have I am sure.

I plant onions the first of April. I plant them in the garden. I don't start my own. The long day onions will be bulbing in late June and July.

I can get seed, plants or little bulbs to plant from the store.

Seed, planted the first of April will make bulbs but they are not usually vary large, maybe golf ball size. They do make a lot of very nice scallions.

Plants or bulbs planted early April will make a nice large bulb.

Now for you, I would suggest if you are going for large bulbs, you likely need short day onions and you would do well to plant plants or sets now, directly in the garden. They will then bulb up in the short days of April and May.

I suspect it gets too hot there in July and August for onions to do well?

If you are going to grow your own plants from seed for later planting out, I suggest starting 8 weeks before the date you want to plant them out.

By planting the seed directly in the garden, you can actually gain some time as it does set plants back some when transplanted.

At this point you would do well to just plant the long day seed directly in the garden. It should do OK. For that matter plant all your seed directly in the garden. Its too late for starting them as others have said. Try to not get them too thick, but you can later pull some for green onions and thinning and let some go for bulbs.

Good Luck
Gardening at 5000 feet elevation, zone 4/5 Northern Utah, Frost free from May 25 to September 8 +/-

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Greener Thumb
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Location: Monterey, CA.

For the bunching type do I sow a bunch of seeds together in 1 hole? I think I might wait until fall this year and make a bed just for onions. I am not going to try the Long Day variety. I will just look for another short day. I already have seeds for Walla Walla and the Spanish Sweet but have not researched if they are Short Day, but will do after this post. I have American FLag onions which are like a scallion type onion. I have some scattered here and there throughout my garden and get volunteers too. If I let them go a whole season, come Spring they flower. If I pull them up they have somewhat of a bulb.

I recently planted some Egyptian Walking onions a few months back from small bulbs. They are doing ok. I am not really interested in scallions cause I got plenty but want to try bulbing onions in the Fall. Of all the onions and Leeks I have started they seem to do ok all year round. But I mostly start them when it is cool out.

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

I believe bunching type onions are grown for scallions and they are perennial. They form clumps or bunches from year to year. So I don't think what you want to do is sow multiple seeds in same hole.

Long Days -- when you are further north (or south in Southern hemisphere), sun rises earlier and sets later in the summer so you have Long Days. (I think in NJ we get something like 16/8 at longest... longer than that further north). When you are closer to the equator, the day and night length don't change so much (12/12 along the equator) so these are the areas that have Short Days

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Joined: Tue Jan 01, 2013 8:32 am
Location: hawaii, zone 12a 587 ft elev.

Bulbing onion seeds I plant around October. I can only plant short day onions. I like Texas granex (Maui onion), and red onions from the Univ of Hawaii. They are the best adapted to my climate. Zone 11.

I think depending on where you are located you should only plant short or medium day onions. Long day onions are for Northern climates. What is your zone? If you bought seeds, the back of the packets will tell you when to plant in your zone.

Bunching onions, I can plant almost anytime. But it is slow. It can take a month for them to be big enough to even transplant.

The good thing is that Tokyo negi and Lisbon bunching onions can go almost two years before they bloom. I just cut them to use the tops and they regrow. Here, we use the tops not just the white part of the scallion. Usually bunching onions are pulled when the tops get too fat, then they are tough. You can grow bunching onions from the grocer. Cut off the tops, remove the bulb plate and plant. Roots will regrow in a couple of days. ... -varieties ... make-sets/
Happy gardening in Hawaii. Gardens are where people grow.

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