This dwarf Alberta spruce is showing winter desiccation -- or "winter burn" -- a condition in which lack of water causes trees to lose too much moisture and turn brown or die. (Submitted photo)

Evergreens are beautiful plants that provide year-round interest, especially during winter when everything else is dormant. But to get through the winter, evergreens need a little help during fall to prepare them for cold.

It was a very dry September in the Valley this year and this means our evergreens are stressed and need our assistance even more.

Evergreens are green, of course, because their leaves (or needles) are alive all year long and they have a continuing need for water throughout the year. This continuous need for available water makes evergreens vulnerable to winter burn.

Winter burn (winter desiccation) is a condition that occurs when the leaves lose too much moisture and turn brown or die. This can happen in the winter when the ground is frozen and the roots are unable to absorb enough water, or when the sun and wind are too strong.

There are several steps you can take now to help your evergreens avoid this problem.

• Water your evergreens deeply and regularly throughout the fall. This will help to ensure that the roots are well-hydrated before the winter months arrive.

• Apply a layer of mulch around the base of the evergreens. A layer of 2 to 4 inches of organic material, such as shredded mulch, wood chips or pine needles will do fine. This will help the soil to remain moist, regulate the soil temperature and prevent frost heaving. Frost heaving is when the soil expands and contracts due to freezing and thawing.

• Avoid fertilizing evergreens in the fall. Fertilizing can encourage new growth, which is more susceptible to winter burn.

• Wrap young or tender evergreens with burlap or other fabric to protect them from wind and sun. An anti-desiccant spray can also be used. Anti-desiccant sprays are products that coat the leaves of evergreen plants with a thin layer of wax, which reduces moisture loss and prevents drying out. You can apply them in late fall or early winter. Carefully read and follow manufacturer’s instructions.

• Choose evergreens that are hardy in our area. The valley has a USDA hardiness zone rating of 6A. Any evergreen with a zone rating of 6A or lower should be hardy in our area. If buying new plants, check the tag for zone information.

• Avoid pruning in late summer and early fall. This may cause new growth to emerge which won’t have time to harden off before winter.

• Plant evergreens in sheltered locations. Avoid planting them in areas where they will be exposed to strong winds and direct sunlight. If no shelter is available, a windscreen or sunscreen can be constructed. Evergreen plants are hardy, but when growing in container they need a little extra attention to protect them from the cold.

• Containerized plants are more exposed to temperature fluctuations than those in the ground, so they should be able to tolerate colder temperatures than your zone. A good rule of thumb is to go two zones colder with containerized plants.

Use larger pots with good drainage and insulation. Larger pots have more soil volume, which can help buffer the roots from freezing and thawing cycles. Make sure the pots have drainage holes to prevent waterlogging and root rot.

You also can wrap the pots with burlap, bubble wrap, or other insulating materials to protect them from frost. If possible, move the container into a sheltered location, such as a garage during cold periods.

Even with precautions, winter injury can still happen in severe weather. How can you know if your evergreen has had winter injury? The best time to inspect for winter burn is in the spring after new growth has started. Look for brown or discolored leaves or needles.

If you find winter burn the University of Wisconsin says to prune back the stem or branch to living tissue, gently scratch the outer surface to see if it green. Green means its living and brown indicates it is dead. If you can tell if the brown leaves or needles are a result of winter burn or caused by something else, bring a sample of the evergreen into the Mahoning Extension Office’s clinic for an evaluation.

With a little care your evergreens can avoid the burn and be healthy and beautiful next spring.

For more on winter burn of evergreens:: http://go.osu.edu/winter-burn .

For more information on anti-desiccants: http://go.osu.edu/protectevergreens .

Sprague is an Ohio State University Extension Master Gardener Volunteer in Mahoning County.