On or about the third week of March (depending on the weather), uncover the roses very carefully so as not to disturb any new growth. A hose at half speed will help remove the mulch.
Begin pruning the canes; if there is any dark brown discoloration in the center of the cane, keep pruning down one inch at a time until you reach wood that is only slightly discolored or all white.
At this time, you can work into the soil around the bush 1 cup of Alfalfa Meal or 2 cups Mills Mix. Spray the bushes with a fungicide and insecticide and let dry. Recover the bushes with mulch.
After the last frost date (April 15-23), you can begin to gradually pull the mulch away from the crown. Be careful not to damage any new growth. (White basal breaks will be damaged by the sun, so they should remain covered until the tips begin to mature.)