personally, i would go for the sunroom - keep them properly watered. it also depends on the cultivar - some roses are more tolerant for frost than others. it really depends on what kind of temperature range your sunroom will experience, but if it is attached to the house, it might still be warm enough. i also asked the same question in my own thread (see down below in the same forum, and similar lack of answer because it all depends on the judgement of the gardener) - p.m.

Do you have an unheated garage or shed? That would be a good place for them to winter as long as you water them a little every month. I just think that that sunroom, even though cool, will be to warm and bright and they'll just keep on trying to grow in unfavorable conditions and exhaust themselves and die. Otherwise, for my money, I'd put them outside in the most protected spot in your yard and bury them in soil or mulch. Or even just dig them into the ground.

Hi EllaRose: Bluegirl in Texas posted a great tip on how heat at the bottom encourages root growth, see link below.

Roses die in my zone 5a mainly due to: 1) fluctuations in temp., thaw-and-freeze, and a sun-room will do just that: hot sun during the day, and freezing temp. at night. My house has 22 windows, most face southern exposure. It gets above 70 degrees during the day with sunshine, then dips to low 50's at night. That's hard on plants.

2) Roses also die due to dryness in my zone 5a. The root balls, if buried in deep in wet soil outside, won't dry out. The root balls, if covered in a dark garage, and watered once a month, won't dry out.

3) Indoor plants: You have a HOT basement ? If there's a window, roses can keep growing, but there are many drawbacks: too dry, and you'll get spidermites. Too wet, or misting with sprayers, and you'll get black spots. I'm not sure if it's worth it. I kept herbs in a basement (with a window) and I'll never do that again. White flies, black canker from over-watering, not worth it.

I agree with Seil that keeping them dormant (dark & cool) at a stable temp. is best. Freezing and thawing is hard on the roots. See link below for Bluegirl's excellent tip on digging a pit to shelter rootings in Texas fall weather.

Here is a link that might be useful: Hot beds for fall rooting by Bluegirl

This post was edited by Strawberryhill on Fri, Oct 25, 13 at 13:31

It may be too late for this information.
I would dig a hole and put them into the ground for the winter. I do this with any new roses I may have gotten in the fall. They will be just as green as the day you put them in!
Mark the place where they are so you remember!