There are many factors in helping your roses overcome the frigid temperatures of winter.The first thing to consider is the location of your plants: Are they located in a protected area, such as against the side of your house or outbuilding or in an open spot more prone to windy conditions?
The most common misconception is that roses need to be kept warmer during the winter. This is simply not the case, and the protection we give them is to actually keep them in a cooler state so they are protected from coming out of their dormant state during a winter thaw. They generally need help over the winter in areas where the temperature goes below 25 degrees.
Try to plan on winterizing your garden around Thanksgiving weekend. That is generally past the time when the weather is going to significantly warm up. Also, do not winterize your garden too soon, or you will actually keep the roses warm and prevent them from going into their dormant state.
Save your heavy pruning on your roses until spring. Pruning too much will only encourage the plant to grow new leaves that will only become damaged by the winter.
The last feeding for your roses should be about sixty days before the first frost.
When preparing your roses for winter, be sure to clean up all dead leaves that could harbor disease over the winter and throw them in the trash. Then hill up the area around the base of each plant about 12 to 15 inches with horse manure, mulch, compost, shredded oak leaves, etc. This method will protect the canes inside and also provides some good soil enrichment in the spring when you push the hill away from the plant.
Snow is actually very good for roses. It insulates them and keeps them at the same temperature so they don't start growing too soon before winter is actually over and it also protects them from harsh winds that can harm them.
Keep in mind that the overall health of your roses is key to them surviving the winter. Healthy roses that were fertilized and watered through the season and are kept free from disease and damage by insects will get through our winters better than those plants that were neglected.
