MEEKS: Protecting plants against cold temperatures
Jack Frost is knocking on our door. It seems that winter will be here before we know it. During the cold days of winter, there is nothing like snuggling on the couch with a hot cup of tea, but the fun begins when it's time to protect all of the outdoor plants from the freezing temperatures.
Plants naturally begin to acclimate themselves for cooler temperatures during the late summer and fall. This is triggered by the shorter days and cooler temperatures. If this process happens too fast, the plant's growing season is shortened; too slow and the plant will be injured or killed by frost.
Several factors including local weather conditions, plant selection and maintenance practices during the growing season can affect the timing and extent of cold acclimation of landscape plants.
The best way to prevent cold damage is to select plants that can tolerate temperatures in your climate zone. In addition to proper plant selection, site selection is essential. During the winter, warmer spots are often found on the southern part of the property and colder on the northern. Cold air will also settle in low areas.
Plants that have proper nutrition have a better chance of surviving frigid temperatures. A soil sample is the best way to determine the fertilization needs of your plant. Fertilizing plants at the proper time of year is also vital. A fall fertilizer application with nitrogen can cause a flush of new growth, which is more susceptible to cold temperatures.
Pruning in late summer or early fall also can cause a flush of new growth that can result in cold damage. A general rule of thumb for pruning: spring-flowering plants should be pruned in the late spring after they flower; summer-flowering plants should be pruned in late winter/early spring.
You can protect plants in containers by moving them into a protective structure or by placing a cover over them. Because their roots are exposed to air temperatures, plants in containers are especially susceptible to the colder temperatures.
Containers left outside can be pushed together and covered with mulch, burlap or a blanket to reduce heat loss. Be sure to also wrap the containers. Plastic sheeting is not recommended; the plant can heat up rapidly as the temperatures rise during the day. Remove the cover and provide ventilation to the plant during the day. Building a frame helps keep the cover from coming in contact with the plant and possibly breaking leaves and stems.
Plants growing close to the ground are usually protected by heat radiating from the soil.
Plants continue to have water need throughout the winter. Also moist soil absorbs more heat. Cold damage may not be apparent for several days or weeks. Cold damage will cause discoloration to the damaged area. Wait to prune any damaged tissue until after the threat of a freeze has passed to protect possible live tissue.
For more information on any program area, contact Houston County Extension at 478-987-2028 or drop by the office at 801 Main St., Perry. Office hours are 8 a.m.-5 p.m., Monday through Friday. Visit the website at www.caes.uga.edu/extension/houston/ for more news about your local Extension office.