Protecting Plants from Winter Damage

photo by Peter Knorzer
The most effective way to prevent girdling and other damage by rabbits to trees and shrubs in winter is to install tree guards or hardware cloth fencing around vulnerable plants.

by Deborah J. Benoit, Extension Master Gardener, University of Vermont

NORTH ADAMS, Mass. – With snow on its way, are you wondering what else you can do to prevent winter damage to your garden?

The first thing is to be sure your soil gets a good drink of water before it freezes. This will help prepare both soil and plants for the coming winter.

Once the ground has frozen, add a thick layer of mulch to help insulate the soil and regulate temperature fluctuations that can cause frost heaves when there is insufficient snow cover. After a period of mild temperatures, the ground can begin to thaw.

It’s those freeze-thaw-refreeze cycles that can cause the ground to heave. Severe heaving can push plants and bulbs out of the ground, exposing them to more damage than they would be subjected to otherwise.

Sometimes it’s the things you can’t see that do the most damage. Little rodents can move unseen under the cover of snow. Rabbits hop along its drifts. Hungry deer wade through snow under cover of darkness to provide an unwelcome pruning. The one thing they all have in common is the damage they can do to plants during the winter months.

Young trees can be killed by mice and rabbits that eat the bark completely around the trunk (called girdling). To help prevent them from nibbling on the bark, fit flexible tree guards around the trunks of your young trees.

photo by Karsten Paulick
Rhododendrons and other landscape plants can be protected from winter damage with a wind barrier made with burlap and stakes or, for a single plant, a chicken-wire tube wrapped in burlap and tied with twine.

For larger trees with thicker trunks, fashion a tube of hardware cloth. Be sure the tube is several inches larger than the diameter of the trunk. Place it so that it extends from below the surface of the soil to discourage mice to at least two feet above the usual level of snowfall to discourage rabbits.

To deter deer or other animals that might chew the ends of branches or evergreen boughs, you can use various barrier methods, including fencing at least five to six feet high closely encircling the plant or a covering of netting over shrubs and smaller trees.

To protect a larger area, you will need a fence eight to 12 feet high to keep deer out. For more information on preventing deer damage, visit go.uvm.edu/winter-deer.

We’ve all heard the old expression, “It’s not the heat, it’s the humidity.” Well, in the case of one of winter’s unseen dangers to our plants, often it’s not the cold, it’s the drying winter wind. Evergreens are particularly susceptible to desiccation (the drawing out of water from the plant) if left unprotected in a windy area.

To protect multiple plants, construct a wind barrier using burlap and stakes. For a single plant, a chicken-wire tube wrapped in burlap and tied with twine can be constructed around plants in particularly windy areas.

Sometimes it really is the cold that’s responsible for posing a danger to the garden. Severe temperature drops may damage a plant, so you may want to place a tube of chicken wire around smaller plants and fill with shredded leaves or straw.

In addition, burlap can be wrapped and secured around the chicken-wire structure. This will allow air circulation while cutting down on drastic temperature fluctuations, as well as wind chill.

For more information on protecting plants in winter, see go.uvm.edu/winter-trees.

With a few precautions, your garden will happily weather the winter and be ready to grow when spring arrives.

[Deborah J. Benoit is a UVM Extension Master Gardener from North Adams, Mass., who is part of Vermont’s Bennington County Chapter.