This was a difficult winter for evergreen trees and shrubs due to long cold spells with high winds. Your plants may have suffered desiccation damage, when the moisture is drawn from the leaf faster than plant is able to replace it. In the winter it is especially difficult for a plant to retain moisture as the cold freezing winds tend to be very dry.
Because the ground is frozen the plant is unable to replace the moisture lost until the ground around its roots has thawed. Trees and shrubs that have been planted during the prior growing season are somewhat more susceptible to winter dessication. In the early spring, the best course of action is to wait. Spring awakening for a plant can come late after such a winter. A fundamentally healthy plant will push out new buds and leaves after a difficult winter. If it does not, then it has most likely died. If the plant does push some new leaves, applying a balanced fertilizer to the plant will help it recover during the coming year.
