Protecting Plants During Winter


by Karen Weiland, Advanced Master Gardener



I know many of you are not thinking much about gardening this time of year, but winter weather has the potential to cause much damage to landscape plants. Here are a few steps that can be taken to prevent or minimize winter damage.

Remove heavy, built -up snow from bushes to prevent breakage of stems.

Branches that normally have some bend, can and will break in the winter if they are frozen and get too much of a snow load on them.  Foundation plants are often damaged from ice and snow falling off of roofs onto their frozen branches.  Multi-stemmed evergreens, such as arborvitae, can be wrapped with twine or rope to prevent limb breakage.  This will help the stems support each other.  After heavy snow has accumulated, shake the snow from the branches or brush it off with a broom.  Leave snow at the base of the plant to insulate the roots.

When clearing driveways or sidewalks, take care not to throw heavy snow onto the bushes nearby.   When choosing your ice melting chemical, take into consideration the effect it will have on nearby plants.

During the winter there is a lot of green underneath that snow just waiting to bust out come spring.  The more you can do to protect it now, the better it will look once the snow has melted off and warmer weather arrives.

Winter mulch isn’t critical  for all garden plants, but it can mean survival for some of the less hardy ones.  Applying mulch for the winter protects plants and their roots against wide temperature fluctuations in the soil and extreme cold temperatures.

The soil has a tendency to heave when subjected to wide temperature changes, pushing the plant and roots out of the ground.  Shallow-rooted plants like strawberries and newly planted stock that has not established a good root system are the first to be subjected to the heaving process.

Applying  two to four inches of mulch such as bark chips, straw or pine needles should give your plants enough protection.  More protection may be needed for plants such as roses. (see Purdue publication HO-128 Roses).

Applying mulch too early in the season can smother plants and may invite disease.  It is best to wait to apply mulch until temperatures are consistently around the freezing mark.

The sunny days of winter are a welcome sight to us humans, but that sunshine can cause trouble for some landscape plants such as young, thin-barked trees.  Sometimes the bark will split vertically  on the sunny side of the tree because as the temperatures quickly drop at sundown the outer bark cools down and contracts faster than the inner bark.  Therefore the outer bark must split  to accommodate what’s underneath it.  You can protect the tree by wrapping the trunk with a commercial tree wrap.  I use a length of flexible drain tubing for this job.  Purchase tubing in a diameter that will fit easily around the trunk of your tree plus a little extra and make a cut along the length of it.  Separate that cut and fit the tubing around the length of the trunk of the tree.  Remove it in the spring and it can be used for several years if you buy it big enough to accommodate the growth of the tree trunk.

More information about gardening and related subjects is available online at   The Purdue University Cooperative Extension Service can be reached at 499-6334 in LaGrange Co., 636-2111 in Noble Co., 925-2562 in DeKalb Co. and 668-1000 in Steuben Co.