I asked about this a little while ago and got some good advice. I eventually took it all down to 10 inches or so and it's coming back great, really bushy. Here is a link that might be useful: Pruning Cotinus

Did you kill your lawn by mowing it in the fall? Seriously, ornamental grasses are only larger growing species of grasses closely related to turf grasses and like lawns or turf grasses, easily tolerate routine cutting back. It really doesn't matter what the season is, as long as they are fully hardy for your zone. You could even cut them back during the growing season if you wanted to, although that kind of defeats the purpose of growing them as ornamentals:-) Many gardeners like the effect of the grasses through winter, plus they supply winter food for birds, so leave the grasses in place until late winter or early spring before cutting back and cleaning up. Others, in the interest of neatness or because they have the time now, cut them back in fall. It's your choice.

Pippi21...... I agree with Jim, especially if you are talking about modern roses, which store their nutrients in their canes instead of in their roots. If you prune now, you are cutting off their bread basket and will weaken the rose. It's OK to mulch, but be careful not to allow the mulch to rest against the crown of the rose. We get, on average, 30" of rain in my climate and the ground and mulch don't really dry out until late spring. If I allow the mulch to stay in contact with the base of the rose, I risk crown rot. I usually have to check several times during the rainy season. Smiles, Lyn

What variety of rose is it? A rose of that height doesn't need pruning, and I wouldn't prune any rose at this time of year. In late March/early April (usual guidance is when the forsythia blooms in your area), trim off anything dead and do a light shaping if it needs one. That will be all that you rose needs.