I’m in 6A, but grew onions from seed last year and had better results from seeds, rather than the onion starts.Whee! I just ordered my onion sets. The local big box grocery has Stuttgarter every year, but only once did I find Red Baron there. I tried those, and of course since DH loves those best of all, they haven't had them since.
I got Red Baron sets from Gurney's last year, and I think I ranted on enough about my disappointment with Gurney's. So I looked online and got them from Maine Potato Lady. They aren't organic, but I can live with that.
I've never grown onions from seed. Has anyone here in Zone 5 done that?
There are 3 types of onions: short-day (for southern states), long-day (for northern states), and day-neutral (generally ok everywhere). It has to do with day length…once day length reaches a certain point, the onions begin to grow the bulb (if I’m remembering correctly).
Start the seeds inside. Then plant outside at appropriate time (I think they can tolerate some cold once sprouted and grown a bit). Thin them to get green/young onions. Since I was late putting them in the garden last year, my day neutral ones did better than my long day ones. But, both performed better for me than using the little onion bulb sets.