Will I need to bring the pots in during a frost or freeze?

Not unless it gets very cold. I'd bring them in if the forecast is below 25, but that is just being cautious.

The idea is that the roses enter dormancy in the field, are harvested, and wake up in their new homes. So the big concern is if the new roses are way ahead of established roses. Otherwise, there are some issues with putting them in pots because the roots aren't insulated by a lot of soil. But it is accepted that a certain amount of hauling in and out is going to happen.

Most of the Meidiland ground cover roses should be reasonably hardy even in a pot in zone 6. They're pretty much tip hardy for me in zone 5, so even losing a zone's winter protection by being in a pot still keeps them in a hardiness range. Mad Gallica is right - go ahead and plant them when they arrive outside, and they'll wake up and leaf out when the weather tells them it's OK to do so (usually when the bulbs are coming up).

You might think about how large the pots are for these roses. Ground covers can take up a fair bit of space when they're happy, and I'm having trouble picturing window boxes with enough room. I don't grow roses in pots so I don't know how big is big enough, but you'll need to have a big enough pot to support the roots about as much as the size of the top part of the rose when fully grown.

Sounds like a good plan!

Cynthia

The pots are 15 gallon and the window boxes are about 32 inches width and 20 inches deep.

Ok so I bought the containers inside before the cold freeze the next few nights. When I bought them inside the soil was frozen. I'm worried they will die since the soil was frozen and dry. I bought them in my unheated garage against the wall that is attached to the house, watered and wrapped a piece of burlap and plastic around the container. They will probably have to stay inside for 3-4 days then back out. What should I look out for the next few days? Will they survive?

Guessing you've had your bare root roses planted for a week or more by now? As long as you watered them in thoroughly when you planted & checked the soil didn't dry out completely in the meantime, think your chances are good your roses will be fine. Canes/branches should look about the same as when you planted given the short time frame. What's your weather been like? Was it warm enough for leaves to begin to grow in the last week? If they haven't started to leaf out, they're still asleep in the dormant phase & likely aren't the least bit fazed by the cold. Sue

Yes It's been a week. I did soak them for 24 hours before planting. They are still green. They still look the same. It will be in the teens for a low until Wednesday. Should I put them back out after it reaches above 25 degrees F for a low? Thanks!

Safe to put them outside once the low is above 25. Been some years since doing the new bare root roses-in-pots back & forth between garage & yard here. Went with heavy cardboard boxes cut & stapled to shape to fit over the roses & their containers when cold weather threatened. Easier to store those in the garage than the roses, lol. Still use heavy cardboard boxes to insulate younger roses for those temperature dips when they're leafing out or budding up. Keep boxes folded down flat in the garage so they're ready to be flapped together for quick use overnight as needed. Good luck, Kay, and keep us posted! Sue