Winter cold and winds can be harsh on your landscape. Temperature fluctuations in the winter result in moisture loss for your plants, which can be devastating on your evergreen trees and shrubs that maintain foliage year round. As the ground freezes, transpiration occurs from the needles and leaves, resulting in an increase in water demand. If the roots of these evergreens can’t keep up with this moisture loss, the result is Winter burn or ‘desiccation’—the needles and leaves will turn brown and crispy due to dehydration of the plant.
The same thing happens to us in the winter, and we accordingly apply moisturizers to protect and restore our skin. Plants need the same kind of attention, which is why you should take action to protect your plant. More often than not, this is caused by long dry periods of cold and thaw along with winter winds. So while those mid-winter thaws with temperatures in the sixties may be nice for us, plants take it much harder.
Native plants are usually better equipped to deal with the changes of an unpredictable northeast winter. Some broadleaf evergreens, however, such as holly, rhododendron, cherry laurel, skip laurel, mountain laurel, Japanese skimmia, leucothoe, aucuba and boxwood are even more susceptible to winter drying and long-term damage.
The easiest, most practical way of avoiding winter damage to plants is to apply an anti-desiccant spray to the upper and lower parts of the foliage before the temperatures drop below freezing or during a winter thaw. Anti-desiccant is a sealant that is applied by spraying onto the leaves and branches of the tree. When the material dries it creates a 
protective waxy coating to the tops and undersides of the leaves of broadleaf evergreens to help slow the process of transpiration which causes water loss and winter damage. Applying an anti-desiccant will protect your plants from drying up as the ground freezes and the roots are no longer able to absorb water. This will make all the difference on new plantings and evergreens that reside in open, unprotected areas.
While you can purchase an anti-desiccant at your local home improvement store, it’s often best to rely on the larger spray equipment used by the professionals to maximize the protective coating on your plants. The product will eventually dissolve and break down with warmer weather allowing the plant to put out its new growth naturally. In areas of the country with especially harsh winters, like the northeast, it is a good idea to apply the anti-desiccant in the fall and again in the middle or end of January. So don’t leave your plants out in the cold—protect them from winter burn!