We have been enjoying mild late fall temperatures and our plants have been slow to respond to the normal signals to go dormant. Trees and shrubs finally received the message, yet our lawns remain pretty green and maybe even needed one more mowing before the big snow.
There are some landscape plants that have always needed a bit of help to get through the winter with limited damage. Whether brand new to your yard or established for years, broadleaved evergreens like rhododendrons or boxwoods can be heavily damaged by winter sun and drying winds. If the crystal ball actually worked, it would be telling us to potentially expect more damage next spring as these kind of plants are reluctant to go dormant in a normal year.
There are some ways to prevent or slow the damage to those broadleaved shrubs. The first thing is to be sure they are well-watered as we enter the really cold days of winter. A temporary winter wind screen will slow the drying winter winds, in turn slowing water loss through the leaves of our broadleaved plants and the and the needles of our evergreens.
In addition, organic mulches have several great qualities to benefit plants. The one that will be in play more this time of year is how they slow the change in soil temperatures, allowing a longer time for the plants to adjust to our winter weather. Additionally, the mulch will help retain that good soil moisture after you have been watering. The root system will absorb and move as much water into the leaves and needles as possible. While a mulch layer during the growing season should be only 2- to 3-inches deep, mulches for the winter can be deeper with the expectation that you will remove the extra next spring. The deeper mulch will provide additional protection. Remember not to place the mulch up the trunk of trees or fill in the base of shrubs. Rodents love to live and eat under the cover of that mulch.
Another direction to go is one of using an anti-desiccant spray, especially on broadleaved evergreens. These materials actually protect by forming an air tight seal over the leaves, preventing water loss. Always read and follow product labels, which provide much information, including how best to apply and benefit from their use. Typically, they are applied on days above freezing and may need to be reapplied very early next spring or late winter to provide the protection we want.
When you have done all you can to protect newly planted and established winter sensitive plants in your yard, Mother Nature also can help. Plants buried in snow are much more protected that those out in the open with bare ground. To encourage that, perhaps snow fence strategically placed in the landscape is in order.
One last thought: Be sure to remove the garden hose from the house so your frost-free spigot remains that way. After that final watering, drain the hose before storing it for the winter.
About the author: Richard Hentschel’s expertise extends across several subject areas with specialties in lawn care, fruit tree production, woody ornamentals, and home and community gardening. During his 45-year career in horticulture and agriculture, Hentschel became a well-known and respected expert for commercial and homeowner audiences, industry organizations, and media. He retired from University of Illinois Extension in April 2022 with nearly 30 years of service as a Horticulture Specialist and Educator in northern Illinois.