Growing onions from seed, questions.

[MOFISHIN]

I've been researching this the last couple of days, and my head is kind of spinning. I'm in zone 6A. It sounds like intermediate onions would be my best bet. But do I start my seeds in Spring or Fall? Indoors or directly sown in the ground? Could I start some now and have them ready to eat before our first frost, which I believe is usually late October?
I've read so many things, I'm not sure what to do. I was thinking of going with red onions, if that makes a difference.
Thanks.
Oh, I almost forgot. One thing I read is to have them at "cool room temperature" when starting indoors. So, I'm assuming my heat mat won't be necessary?

 

[Chuck]

You should start your seeds in the late summer to mid fall. By the time your soil is workable in the early spring or late winter your seedlings should be large enough to withstand any late frosts or freezes. Onions are either long day, short day or intermediate. I am not sure exactly where you are located but I would not plant intermediates. If they were that successful they would be recommended. I am pretty sure you are in the long day varieties and it doesn't make much difference whether the varieties are red, white or yellow. It is the day length which determines bulbing. You can forget about planting seeds now and having green onions this winter unless you want midget green onions. Start your seeds in flats very thickly. The soil in the flats should be about 1 1/2 - 2 inches deep. and self draining. When they are about 2 inches tall fertilize them 1/2 strength with a good liquid fertilizer like HastaGro from the bottom up. Fertilize again at the same rate when they are about 4 inches tall. When the greens reach about 6 inches tall fertilize full strength. By the time they are ready to transplant they should be about 8 inches. Pull them out of the flat by handfulls. You may have to soak them in water to seperate them because the roots will be all entangled. You can also snip off the bottoms of the root systems to make the separation easier. Browning of the leaf tips during this time is normal. Just get some sizzors and snip off the tips. Before setting them out soak them in a mixture of 3 oz liquid seaweed per gallon of water right before planting for about 1/2 hour. I plant them with about 1/2 of the white showing deep. Keep watered slightly more than usual until they have new leaves and then reduce watering to as needed. Onions are heavy feeders and what you want are as many leaves as you can get. Don't worry about not seeing a bulb. Each leaf = one ring on an onion. don't be surprised if it takes 110+ days to maturity after transplanting. They will be ready to harvest when the leaves of the plant fall over. If one starts to flower, harvest it then and there. And keep them well fertilized with a good organic fertilizer. Oh I forgot. The best soil temperature for sprouting onion seeds is about 75F