Prevent winter burn by knowing requirements
Each spring the clinic receives calls and specimens of evergreens that have dead areas on the branches. It is so important that these be diagnosed correctly in light of boxwood blight and other diseases that can cause serious issues and even plant death. The first diagnosis that can be identified is winter burn. The plant loses necessary water due to sun or wind or both during winter and cannot uptake enough water to recover. This desiccation damages living tissue.
Evergreen plants are pines, spruce, arborvitae, rhododendron, azalea, false cypress, boxwood, holly, fir and many other plants that do not lose leaves or needles in the winter.
When a person buys an evergreen to plant in the yard, the information and research have special requirements — zone, some shade versus full sun, moisture limits, soil conditions, protection, etc. — that are so important to that plant thriving. These instructions must be adhered to for the plant to be the best it can be and last for years to come. So, let’s look at these important instructions:
Plant in the correct situation — zone, adaptations, soil conditions, sun intensity, shelter locations, etc.
Plant either in the early spring or the early fall as the roots need time to grow and establish, as well as for watering; this is a must.
Never prune in the fall because this will trigger new growth that will not harden off in time to stay healthy throughout the winter.
Make sure fall watering is well done and consistent.
Mulch well about 2-4 inches deep around the drip line and 3 inches out from the trunk. This helps hold moisture and will forgo spring heaving that can damage tender roots.
Never fertilize in the fall as this triggers new growth that will freeze.
Protect plants with loosely wrapped burlap, canvas and snow fence leaving the top open for air circulation; remove when spring settles in.
Existing plants can be taken care of for winter using these tips. Take advantage of the nice weather and add some mulch as you can. It is late to do this, but it can help some.
In spring you may see browning on one side or a section of your plant. It begins at the outer edges and moves into the plant center. Usually, the southwest or west are most affected.
When snow melts in spring, the foliage appears brown. Scratch the bark along the leaf to see green (will recover) or brown (is dead).
You should trim back to living tissue (green) or it will fall off, and in a couple of years, the plant will recover.
To learn more, go to: https://go.osu.edu/avoidwinterdamage.
Hughes is an Ohio State University Extension Master Gardener Volunteer in Mahoning County.