Frost, cold wind and winter sun are putting the roses in a lot of distress. Therefore, they need to be protected and well wrapped.
Effective protection for sensitive roots is achieved by earthing them up. This refers to covering the plants with a 6 to 8 inch (15 to 20 cm) high mound of garden soil or compost.
Protection against desiccation
Much more dangerous than low temperatures is the exposure to wind and sun. If the ground is frozen, the roots of plants cannot work. The shoots will be dried on clear winter days by solar radiation and wind - losing moisture that can not be replaced by the roots in the frozen ground. The roses therefore do not freeze to death but dry up. A solution could be covering the plant with burlap or fabric to protect it against strong sun rays.
Winter damage to floribunda and hybrid teas that are pruned in the spring anyway is less bad. It is much more annoying if long shoots of climbing roses get damaged. Climbing roses on walls can be covered with straw mats.
High stem roses particularly vulnerable in winter and require particularly good protection. Cover the crown with a suitable fabric and tie it below the crown base. Do not use air-tight plastic wrap, moisture and heat accumulates underneath.
Potted roses overwinter in a sheltered, half sunny spot a warming pad, for example using styrofoam.