Onion and leeks planted in fall

Hello! Looking for advice in planting Walla Walla onion and leeks in the fall.  I am in zone 6a. Do ya'll plant these in the fall? If so, when? And do you see good results with planting the Walla Walla from seed ( which is what I have).  Thanks!

I'm going to be trying it planting leeks in the fall as well (I'm zone 6 a/b). I interplant stuff and my leeks are always shaded all summer long and stay tiny seedling anyway and don't ever really grow big until everything else in the garden dies off when it gets frosty. So my hypothesis is that I'll get the same growth anyway if I start them later. We shall see!

The leeks and onions will most likely survive the winter but probably will try to flower in mid spring so they may not get very large. Some onions might rot over the winter.

I have several packets of onion seed & recently found out it doesn't keep very well for the long term.  So, I though about trying to grow onion "sets" with them by planting in the fall, then harvesting before freeze up.  My theory is that they won't grow to more than an inch across by then.  Then, cure/dry them over winter like I would spring planted onions.  That way, come spring, I have onion sets that will produce next years' spring planted crop.  I may not have any viable seed, or it may not work the way I'm thinking.  Either way, I don't have much to lose on old seed.

Cy Cobb wrote:I have several packets of onion seed & recently found out it doesn't keep very well for the long term.  So, I though about trying to grow onion "sets" with them by planting in the fall, then harvesting before freeze up.  My theory is that they won't grow to more than an inch across by then.  Then, cure/dry them over winter like I would spring planted onions.  That way, come spring, I have onion sets that will produce next years' spring planted crop.  I may not have any viable seed, or it may not work the way I'm thinking.  Either way, I don't have much to lose on old seed.

I've been given to understand that onion sets tend to produce small onions. Since they are a biennial, they want to flower in their second year of growth, which is the stage that sets are. So sets will put more energy into flowering and not so much into bulb growth. I could be wrong, as I am still trying to understand how to grow onions myself. I will say that I had also heard the seeds don't store well and planted some that were probably two years old and they still had pretty good germination. I'd try planting them in the spring.

My family has grown onions from sets for decades since that's all you could get locally.  We've never had a problem with small onions, but we didn't crowd them either.   In fact, they grow to be just like the ones you buy in stores.  We grew red, white, yellow, & Vidalia yearly.  The way I look at it,  sets are just like garlic cloves in that you get a bit of a head start on the season over seeds.  I could be wrong though.