Remove the dormant plant from the pot, and roll it in burlap. Prune away all of the old foliage above the new bud growth.
Roses have a bad reputation for being susceptible to fungal diseases.
This is true of plants grown indoors as well. The most common disease of indoor roses is powdery mildew. To keep plants healthy, provide good air circulation near your plants, and water only in the morning. A homemade treatment for powdery mildew can be concocted from a solution of one part alcohol-based mouthwash and three parts plain water. Mix the two ingredients in a spray bottle, and apply to the leaves daily.