For the first time im going to plant onions from seed under grow lights.I usually buy onion plants in April to plant.
What method do you use to broadcast the seed evenly without planting one very small seed at a time?

I had great luck, planting into the 18 to a flat 2 3/4" deep cups, the kind you get a sheet of and break apart, or cut with a scizzors....a pinch of seed (12-15 or so) upon a 2/3s full cup, then top it off....I got this idea, because, as you'll note, that is how the onion plants come....bunches, as though planted in clusters of seed....when they come up, and get tall, trim them with a scizzors, periodically, and the bases will grow. Start now or anytime in February/early March...not a big money maker in the greenhouse as it all computes to how much money can you make per square foot...but does grow nice seed.

YOu could have them in a greenhouse micro climate of their own away from all your other stuff...they need warmth at night, not so much during the day.

Trenches in place
moist a paper towel and on the end of the sheet pick up seeds that are laid in a line
place over the trench and cut the paper towel into trench and back fill
watched a old couple that would do 100,000 kelsey onions that way = 3 acres of planting when all was done.
they used old water bed heaters under the table for night warmth = 100*F warmth

Never bothered with seeds. Our best results come from bulks.

https://youtu.be/LyyZ67CTHvc

This method seems to work well for me. I will sprinkle 100 seeds or more in a cool whip container filled with starting mix and then pull them apart when I am ready to plant. Onion seedlings are very tough.

Salt shaker to broad cast. Size of hole determines how thick they are.

You can salt down a trench with quite a few seeds and transplant them when they're a couple of inches high to the correct spacing.

Sprinkle seeds in a tray and cover with 1/4 mix. keep moist and they will germinate at room temp , 68 degrees. Light or bottom heat is not required for germination but light (daylight or 10 hours grow light) after germination is for photosynthesis. As already stated....onions are tough. pull apart and plant when ready.

Thankyou for the answers.

And presto, just like that, little onion plants.

Germination in eight days or less, nice.

Now don't be hollerin about a 900 dollar lektrik bill.

When I’m planting really fine seeds, like carrots, I blend the seed with sifted wood ash from the wood burner. Makes it a lot easier to scatter them.

When I plant turnips I mix the seed with cornmeal and broadcast works real well

Wood ash is called Potash, an ingrediant in most all fertilizers, carefull, too much of a good thing will change the PH.

Looks great! I used to do that same thing but in wooden trays I built and used them for years. The one great thing about starting your onions from seed is you can have any variety of your onion of choice. They grow fast and are heavy feeders and nothing to get baseball to softball size onions. I always raised sweet varieties/yellow and walla walla.

You will be able to cut all the tops down if getting to tall. They will get a larger root base if you do that. Like cutting grass with a scissors.

Good Luck and I miss that alot.

Hair trimming is quite a necessity for onions and their root systems

I have some started for the first time in years. I have set plants out this time of year usually under a row cover. Trying to get back into gardening, life got busy and screwed up and gardening got dropped for awhile. I have put out a small garden the last couple of years just pulling mulch back and planting. I've moved so will still be planting mostly at the old place while I get something started here for a garden, moving from sand to red dirt.

Yum