As we’re putting up Christmas lights before the snows come back and pulling out dead annuals, don’t forget your rose bushes.
Sometime between now and when the leaf buds begin to develop in the spring, cut rose canes back by at least a third. In addition, any dead or diseased canes should be cut back to healthy wood. Healthy wood will be green like an apple. Any canes thinner than the thickness of a pencil should also be trimmed off because they will produce poor blooms.
When you are pruning, look at the rose bush and cut out any canes that lead toward the center of the plant, or any that rub against others on the plant.
Some plants may require mulching in the fall after several days of temperatures below 27 degrees. Despite the perception that mulch is applied to keep the plant warmer, it is actually there to keep the plant colder. The main point of mulching is to stop the freeze/thaw cycle that can damage roots and kill plants. It is better for the bushes to stay frozen through the winter, than to keep defrosting.
When you buy roses at most garden centers (and most other kind of started plants, actually), they come with a tag that states how big they grow, what their cold hardiness is, etc. I’ve seen my zip code listed as anywhere from a zone 5 to a zone 7, though most seem to think we’re a 6 or 7 (which means my coldest temperature is negative ten degrees in winter), but I remember years where we got down to negative 20, so I generally figure my plants need to go to make it to zone 5 or below. There are lots of places where you can find out what your zone is, you can click here.
Some nurseries or garden centers sell roses that are grown in a warmer zone and won’t winter over as well, so it’s important to note what zone your plants are in when you purchase them. There are many, many varieties out there that are fine down to -20 or even -40 degrees, so yours may be included in this bunch. Plants purchased for the correct zone will not need any mulch or winter protection.
One last caveat–some plant growers will stretch the cold hardiness a bit to get more people to buy it, so it’s always a good idea to purchase plants that will survive winters at least one zone colder than yours.
If this is your first winter with your roses, it never hurts to err on the side of caution and mulch your roots at least four inches deep with shredded leaves (you can run your lawn mower over them if needed), pine needles, bark–either shredded or chunks– or straw.