Protecting Young Trees from Frost and Snow

While mature trees can usually take what Mother Nature dishes out in winter, young trees are vulnerable to damage. Here are some tips to keep your younger, more vulnerable trees safe through the winter.

Pick Appropriate Trees

Plant trees that are native to your area. While the USDA zone map will help you decide what trees will make it in your landscape, just because something is from the same zone does not mean it will do well in your yard. Before choosing a tree, you must also consider soil conditions, lighting, humidity, water drainage, and wind. Native trees have evolved to live in the landscape you live in. Most areas have a wide range of native trees to pick from. Pick the right size for your landscape spot so you do not have to prune it to avoid getting too big.

Drought Stress Kills

Young trees require supplemental water for the first two to three years of their lives. Roots must grow beyond the root ball before the tree can withstand drought. Drought stress is the #1 killer of newly planted trees. Before the soil freezes, water deeply around the tree, from the trunk to the edge of the drip line. Moist soil can hold more warmth than dry soil. Water your tree deeply every two weeks or so if there has been no rain or snow. Pick a day when the temperature is higher than freezing, if possible. Water in the morning so the water has all day to soak into the soil before the cold night.

Check The Mulch

Mulch insulates the soil under it. You should have spread mulch in a donut shape, starting three inches from the trunk and moving to the dripline when you planted your tree. Mulch moves around with the wind, rain, and digging by animals. Check the mulch around the new tree in late fall and top it off if there are not at least three inches of mulch there. Make sure no mulch touches the tree trunk, where it will cause rotten spots.

Protect From Hungry Animals

Wildlife has to eat, even when it is cold. Animals that do not hibernate, such as rabbits, porcupines, and deer, get hungry when cold weather hits. They will eat plants they usually wouldn't touch. Tree bark is definitely on the menu. To protect your young trees, place hardware cloth in a ring around the tree and about six inches from the bark. The hardware cloth should be at least 24 inches tall to keep rabbits from hopping over it. Deer can reach over the fence but be stopped with an electric fence wire on the top of the hardware cloth. Keep weeds and grass cut short near the tree trunk. Rabbits, voles, and mice do not want to cross bare ground to reach their food because a predator can see them. After heavy snow, remove the snow with the hardware cloth so the rabbits can't reach over it by standing on the snow.

Wrap To Prevent Sunscald

With no leaves to shade the trunk, young deciduous trees are vulnerable to sunscald. The best way to prevent sunscald is to use a paper tree wrap. Wrap the trunk from the ground up to just under the first sizable branch. Wraps should be on the tree from right before the first freeze until after the date of the last freeze in spring. The wrap must be taken off in spring to keep the trunk from expanding as it grows. All young trees should have their trunk wrapped the first two years after planting. Young trees from thin-skinned trees such as maple, ash, linden, apple, and peach should be wrapped for the first five years after planting.

Pruning

Pruning has two functions. One is to remove any diseased or broken branches before they fall on someone or do other damage. The other function is to train the young tree to grow in a way that will resist wind and rain, will grow into a pleasing, and, in fruit trees, will bear lots of delicious fruit. Young bare-root trees will need training cuts when planted. They must be pruned to help them grow strong in subsequent years. Do this pruning after the tree dorms and before the sap rises in the spring. Late winter is ideal. Pruning after the sap has risen makes it harder for the tree to heal. Insects may be drawn to the smell of sap dripping from a cut and attack the tree. Slowly and improperly healed cuts open the tree to diseases, as well.

Knock It Off

Heavy, wet snow can break young branches. Young evergreen trees are particularly vulnerable because the needles catch the snow. Shaking the branch to remove the snow is not recommended. Use a broom, sweep up under the branch, and lift the boughs to knock the snow to the ground.

Desiccation Injuries

Evergreen trees are particularly vulnerable to desiccation injuries. Deciduous trees can have them, but evergreens are most at risk since they don't go dormant. Spray vulnerable evergreen trees with an anti-desiccate spray in late fall on a day that will be sunny and over 40 degrees for several hours after the spraying is done. The spray coats the needles and leaves with a coating stripped off one molecule at a time by the wind. The needle surface is not disturbed by the wind, so water is not wicked from it by the wind. If your winter lasts that long, you must reapply the spray after three to four months.

Wind Breaks

In general, if you plant a tree that cannot be managed against the wind, you have planted the tree in the wrong place. However, winter storms can be severe, and young trees do not have thick bark to protect them. You can wrap burlap outside the hardware cloth fence you put up to stop animals from eating the tree bark or place burlap or fabric drift fences around the tree.

Winter Care Questions Answered

If you have winter care questions, our staff at Garden Plants Nursery can answer them. Call 931.692.7325 to ask questions and place orders.