Hostas need to go dormant. I assume you have them growing outside, if not harden them off for a month or so before you do this.
Wait until Fall--just before freezeup and plant them pot and all in the ground. By then all the nasty bugs that would have chewed on them will be gone. After the ground is frozen mulch the pots. If you do it sooner you might have an unwelcome guest--like a mouse or vole--making their winter home there and chewing on your plants all winter. Next spring you can dig them up and either keep them a while or plant them out.

I assume this also works for other small perennials? I have a bunch - mostly meadow-type plants like shasta daisies, rudbeckia, yarrows, etc, but some others. They're doing well, but they're still small enough that many look happy in quart yogurt tubs.

I've decided to make a lasagna bed for them over a weedy patch near my driveway. But since I haven't made it yet, I'm thinking the active composting won't be good for the seedlings. I was guessing digging them in somewhere, pots and all, would be the right approach. Would that work fine for my seedlings, too?

Shellhoya, I'm jealous. My hostas were the only real disaster - I got low germination, even with cold stratifying the ones that didn't sprout. Others died one by one from all sorts of problems.

Sure candogirl. Planting pot and all is a good way to keep perennials until the sprimg. Just remember to mulch after freeze-up. Mulching will protect the roots from extreme cold. I use dry leaves and don't cover the whole plant. I make sure there is a bit sticking out. Don't be too anxious to remove it all after the snow goes. Leave the roots still covered but the plant uncovered

Thanks oilpainter for the suggestions. I will have to build a new bed just for these babies. I was wanting to make a slightly raised bed anyway, with maybe 2 high landscape timbers for the edges, and add some decent soil since the ground around my house isn't terrific. Do you think I could build the bed when I'm ready to plant the pots, just sit them in there and add the new soil around them? Or should I make the bed now and let the soil settle in for a couple months? On the same note....Candogal, what is a lasagna bed?

I'm including a link to a couple of my favorite baby hostas. Hopefully you can see the size difference I'm talking about. Some of them are so tiny still! The ones pictured are in 4 inch pots, to give you a point of reference.

Can't get the picture to embed, so here's a link. Hopefully it will work!

Here is a link that might be useful: my favorite hosta babies

You're welcome shellhoya. You're Hostas look nice and healthy.

Yes you can just put soil around your plants, If you water the soil that will help settle it in. Then you can add more if you need it later. The mulch you add later will fill any voids.

As to what a lasagna bed is--It is a neat way of creating a new bed with composting. particularly good for raised beds. You put your raised bed together on top of the ground. Then add a good layer of newspaper or brown cardboard all over the bed--this smothers the weeds. Now you layer in organic matter: much like making a lasagna.

There is lots of info on this site. Just type in no till gardening in the search box at the top of the page.

Oilpainter - Thank you for the tips. Sounds like I was on track. I feel better knowing I can tuck my babies in safely!

Shelley - Your hostas look gorgeous! Now I'd love to pick your brain and find out exactly what you did. I really want to start hostas and have it work this coming winter.

Sounds like you WinterSowed them? I did that for a few things. I learned about it around January, which made it a little late to start. The plants I WS'ed did very well, though. I'd love to hear what you did - medium, containers, etc. Did you post details as you did it? I could search back if so.

Oilpainter did a good job covering the basics of lasagna/no-till bed preparation. Since I've finally gotten going with starting from seed, I can afford to expand to the gardens I've always wanted. I've never done the no-till thing before, but it's going well. A local appliance store will give me as much cardboard as will fit in my station wagon, leaves & grass can be had at the dump, and a local horse owner bags manure & leaves it out for the taking. Makes the whole thing pretty easy. I was already pretty into composting, so it seems natural. (My DH & kids built me a 3-bin set up for Mother's Day - they knew what I really wanted.)

My question for Oilpainter about over-wintering my perennials in a different place was because the process of composting generates heat. The way it happens in no-till gardening isn't as hot as I get in my bins (which get up to 150 degrees), but I'm guessing it's still too much warmth for perennials which should be going dormant for the winter.