Hi! Back on the forum after a long absence. I'm in Zone 7b, and we've had some crazy weather lately (last week it was nearly 70, this week in the 40s). So I put my jugs out later than usual this year. So not totally sure about your first question as far as "when" in Zone 8. I posted earlier about some native seeds that I just put out a few days ago (used to put these outside in December) so waiting to hear from anyone about that. They're probably fine out there, but just double-checking since it's been a while since I winter sowed, and a lot of the natives need at least 60 days of cold moist conditions, so just a little concerned.

But for your other questions:

Container Location: I used to put my jugs in a sunny spot on an uncovered patio for the winter in the Mid-Atlantic, but I was in Zone 6b then, and those years we had very cold, snowy winters. Then once the seeds sprouted, I moved the jugs to a partial shade area under a tree. Now I'm in Zone 7b, so I put the jugs in light shade for their winter stay. Since you're in the warmer Zone 8 in the South, under the oak tree might be a better bet, especially in the late winter to early spring.

Here's a link to a chat about containers and sun/shade:

http://forums2.gardenweb.com/discussions/1680459/do-ws-containers-need-shade?n=10 

Soil: Seed starting mix: I've never used it for winter sowing. But I think it should be fine. I've heard of other people using it with good results. My only thought is that it could present a slight problem when you remove the "hunk-o-seedlings" from the container. Seed starting mix is so light and fluffy that it may not really clump well, making the "getting the hunk out of the container" process somewhat difficult. Unless you've layered the seed starting mix over some potting soil, the whole hunk might just kind of crumble during the removal-from-container process. But if the mix is damp, hopefully it will pretty much hold together during the "extraction process" as I like to call it. And the bakery containers might be easier to extract the hunk from than jugs, which are pretty stiff.

For winter sowing, I usually just use regular ordinary potting mix. Right now I'm using "Espoma Organic Potting Mix" which is just what my local hardware store happened to have in stock. I think I used to use "Miracle Grow Potting Mix." The one thing you definitely DON'T want to use is any soil that says "Weed Free" on the bag. That stuff has chemicals in it that kill weeds (and your seedlings.) Definitely avoid.

Also, I would probably avoid any potting soil that contains hydrogels or some other type of "moisture beads" especially if it tends to rain a lot in Alabama in the spring. Too soggy.

Here's a link about soil options:

http://forums2.gardenweb.com/discussions/1668733/what-potting-soil-do-you-all-use?n=12

Damping off/Cinnamon: Never heard of cinnamon sprinkling to prevent damping off. That's really interesting. I'll have to try that. But I actually never had any damping off when I used the outdoor winter sowing method. Once in a while, I'd get what looked almost like moss growing on the surface of the potting soil. But no damping off. Good drainage in your containers is important. Not too soggy, not too dry. Here's some info on damping off / fungus in case this helps:

http://forums2.gardenweb.com/discussions/1712645/sprouts-and-fungus?n=4

Once it starts getting warm out, the thing to really be careful about is not letting the containers get too hot, which could fry your baby seedlings. And so, the springtime opening and closing process of the containers begins. I make holes for future pipe cleaner closers on my jugs, so I don't have to keep taping and un-taping once the weather gets warmer.

Snapdragons: Have had great success winter sowing snapdragons in the past. They're a hardy annual, so do well with winter sowing.

Your seeds sound lovely! Had not thought about mustards. I love dark-leaved plants. May try those as one of my edible ornamentals--thanks for the inspiration, and best of luck with your winter sowing!

Thank you very much for your suggestions and comments. It was 80 here yesterday. We have broken record highs for the last 4 days. Needless to say, I haven't sown any seeds yet. I'm hoping for a cold snap, but will probably start planting in February regardless. Thank you for attaching the links. I'll check those out today.

You're welcome. Yeah, it seems many in the US are having unusual weather for January. February sowing sounds like a good idea to me. Best wishes and please keep us posted on your experiences!