Yew or Taxus plants and ball-shaped arborvitae are prone to spread apart from the weight of snow. Light rope may be used spirally around these plants to hold them together or a snow shed of boards, metal or polyurethane may be erected over the plants to prevent the snow piling up in the plant. Unless structures of this type are sturdy and sightly, they are often less than satisfactory. Never wrap the plant in polyurethane because the interior will build up very high temperatures during the day that can cause significant winter damage. Boxwood, Japanese holly, mountain laurel and evergreen rhododendrons suffer from heavy snowfalls.
Plants are bent and stems and branches are broken.
The preventative measures of a snow shed like that used for Yew or Taxus would help prevent the snow piling up on the plant. Large specimens are usually on their own with an occasional assist from the homeowner to brush the snow off. A moderate amount of snow is desirable as winter protection. In fact, snow may be brushed or carefully shoveled toward the base of plants for insulation purposes against winter damage from low temperatures. Exposure to continued cold winter wind is another source of injury to boxwood and other evergreens.