Article Copied from the American Rhododendron Society Blog

Print date: 9/26/2017

Winter Protection For Rhododendrons

20 July 2015 @ 00:06 | Posted by ARS Connecticut Chapter

If you haven't planted your rhododendrons in a protected location, you may have to consider providing them with some winter protection! Rhododendrons, particularly large-leafed forms, are sensitive to winter sun as well as winter winds, and if not protected properly, you may have serious damage or lose the plant by spring.

Damage to plants is likely to happened if the plant did not receive ample moisture before in the Fall. During the winter, drying winds and frozen ground deprives plants of their natural moisture intake. The exposed portions of the leaf...usually the central portion when the leaf was curled...may become brown. This may also appear on the edges of some leaves.

To prevent scorch, plants should be well watered in November, especially if rainfall has been sparse; protected from drying winds; mulched well, and given some shade. New plant growth may not have a sufficient amount of time to become woodsy and harden off for the winter. Also, flower buds are the least cold hardy part of the plant.

Rhododendrons, boxwood, azaleas, hollies, and laurel will benefit from an application of an anti-desiccant, such as Wilt-Pruf. Read and follow all instructions. Spraying should occur in late Fall when temperatures are near 40 degrees F. Most anti-desiccants are composed of a "waxy" substance that can break down during winter's thaws necessitating a reapplication.

If you do not get a chance to apply an anti-desiccant, you may want to provide a wind-shield, such as burlap to these shrubs as well as some mulch protection around the base of the shrub. Young plants can be enclosed with chicken wire or dog fencing, and packed loosely with oak leaves. Remove the protection in the spring as buds start expanding. Mature plants can be mulched with several inches of wood chips at the base.

Evergreen boughs can be leaned or tied against plants to limit winter injury. A teepee-like structure constructed with three or four evergreen trees or branches with their points forced into the ground and tips tied together provides adequate protection...or use a burlap covering around individual plants. Snow fencing alone or with a polyethylene plastic sheeting attached to it also gives effective wind protection. Cover the plants just before freeze up in the Fall and uncover after all the frost is out of the ground in the spring.