While you are at it—you may want to save some of your rose prunings and turn them into new plants. Many methods exist but one of the easiest for homeowners is to use a one gallon, clear plastic, resealable bag.
Combine equal parts of all-purpose potting soil and perlite. Moisten lightly. If the mix drips water when squeezed, then too much water was used. Start over with less water. Fill the bag with a two-inch layer of the moistened media.
A fresh cutting is essential to rooting success. When pruning roses, look for stem cuttings 3 to 4 inches long that have 2 to 3 leaves attached. The best stem cuttings are from rose canes that have just bloomed. Place in an ice chest to keep cool and out of direct sunlight. Place different roses in their own plastic bags and label with a marker. I use the plastic bags that protect my Advocate newspaper.
Remove only the bottom leaf and dip the bottom inch of the stem cutting into a rooting hormone, like Dip ‘N Gro or Rootone F. Immediately insert the cutting into the media, making sure the remaining green leaves are exposed to light. A bag will comfortably hold 10 cuttings. Exhale into the bag to inflate and then seal.
Place the bag in indirect light. Direct sun will kill the cuttings. The enclosed bag will simulate greenhouse conditions with a high relative humidity. Condensation will form within the bag. Leave the bag undisturbed for the first week. Open the bag to exchange air and to remove any dead leaves, being careful not to move the cuttings. If condensation fails to develop, add 2 tablespoons of water.
In 3 to 5 weeks you will see emerging roots, and in about 5 to 7 weeks, open the bag to allow the cuttings to become accustomed to outdoor growing conditions. The soil will dry so keep a close eye and water sparingly when needed. Plants can receive additional light now that the bag is open.
Once fully rooted and with new growth showing, remove the cuttings and pot in small containers or directly into a protected garden spot.