Broadleaf evergreen trees & shrubs are susceptible to “winter burn” or drying out damage to their leaves through winter. The combination of cold winter winds pulling moisture out of the leaves, and a dormant root system unable to replenish that moisture can cause the browning or death of some or all leaves. While this won’t necessarily kill the plant, it makes for very unattractive trees & shrubs until the plant can regenerate new functioning leaves the following spring and summer.
This process yearly can greatly weaken the plant and eventually cause death. Our “wiltproofing” protection spray in late fall – early winter is designed to “coat” the leaves to prevent moisture loss and this type of winter damage.