Daylilies can safely stay potted until they become root-bound in the pots. Certainly for at least a year, perhaps a bit more, depending on the size of the pots.

I can think of at least one hybridizer here in central Florida who grows everything in pots.

As for how well they do in pots over the winter, that's a question best left to someone in your zone.

I grow most of my daylilies exclusively in pots. Some are over 7 years old (with yearly maintenance). For your temporary situation I wouldn't worry about them being in a pot over winter. The only thing you need to make doubly sure of is the drainage. They may rot if they are in just regular potting soil - or worse dirt from the yard). Many of them will go completely dormant or mostly so in your zone. That means lots of water on the roots during winter when they aren't growing will rot them. Keep them on the dry side. Just enough to keep the roots from drying out.......Maryl

ok, that's good news! I do have them in regular potting soil, but I think if I move them under the overhang of our barn it should keep them drier than out in the open. Thanks for the advice!

Tammy

ive never done this with daylilies or with any of my own plants for that matter...but a farm/bedn-n-breakfast/wedding venue place i used to work at would overwinter things that didnt fit into their greenhouses inside haybale boxes. they did this with their cannas, elephant ears, banana plants, etc.

a small example would be to take 4 bales and arrange them to where there is an open space in the middle. the more bales, the bigger the space. we would put the pots in the space (or even just bulbs on top of a layer of hay), sprinkle some hay thickly on top and cover it with a dark tarp, to attract the heat.

i think it might be a bit of an overkill for daylilies, but i thought i would pass along the method anyways.

I'm not really zone 7a anymore, probably 6a or b after our move. Some of my daylilies didn't get planted in the winter of 2010-11. And some of them are still not planted. But I did protect the pots from winter sun placing them on the NW side of a stack of firewood. There is some leaf cover during the winter. They have been watered with just rain and the normal watering of the lawn. They have rooted out of the pots into the soil, so I'm leaving them undisturbed for evaluation. They are seedlings. Some are clumps now! As I have selected the ones I'm most interested in keeping, they are moved to the garden.

We do have tall water and pin oaks around the yard which seem to make a warmer microclimate.

I've left daylilies in pots for well over a year. I live in Zone 5a in Canada and in the winter I pile all of my potted plants on the nw side of my house behind the garage in a flower bed. I then put bales of straw around them and pile bags of leaves over top. I have never lost a dayliliy other than one on the top that my dog dug out in the spring. They say it is better to not let them get soaked with water and then freeze but I think some of mine have and they have survived. You can tip them on their sides to keep water out but that makes it harder to stack them up. Putting them on soil lets them drain for as long as possible I think.
My husband has dug some into the ground in their pots before and just let them get covered with snow but that is too much work for me. Might as well have planted them earlier!
Good luck.

Up in zone 5, we give the potted daylilies a little extra protection in winter. We covered them with foam and then opaque plastic, but with just a few, you should be fine with just piling some mulch, straw, or pine straw around them. You may need something to prevent rodents from nesting in the pots as well, either traps that you check regularily or bait.

What you want to prevent is the freeze/thaw cycle where it warms up too much during the day and freezes again at night. That is a sure way to rot a perrennial. I suspect that isn't quite as much an issue in Zone 7 as it is in Zone 5. If you feel up to a little extra work, just sink the whole pot till the top of the dirt in the pot is level with the top of the ground. Then they get the benefit of all that insulating ground around them while still being easy to lift out and move in the spring.

Debbie