With the exceptionally bitter cold winter we have had, cold damage to woody shrubs and trees can be a problem here in Georgia.
It is hard to know exactly how much our plants have suffered through these sub-freezing temps. We will have to wait until late winter and early spring to see exactly what has been affected and to what extent.
Several types of plant damage can occur during the cold months. All parts of a plant that can be affected include the fruit, leaves, roots, trunks and stems.
Leaves and stems usually show the damage first. Ice actually forms within the plant cells and kills the plant tissue. Leaves or stems then become dark and mushy. If the plant went through a proper cold acclimation process — in which plants prepare for winter — the plant can withstand these types of ice formations.
Windy, cold and dry conditions can also cause plant damage. The plant loses water through evaporation. This damage happens when it exceeds normal water absorption, causing the plant to be dried out and scorched. Then leaf burn will show up.
Flower and leaf buds can be damaged during times when the temperatures are low or fluctuate. The foliage is damaged and may cause a reduction or loss of blooms.
If you suspect bud or bloom damage, remove several buds and open them to determine their condition. If the buds are green, they are healthy. If they show signs of browning or a darkened condition, chances are they have been damaged by the cold.
This does not mean the plant is dead. It only means the foliage or buds did not survive the bitter cold temperatures.
This has happened a lot this winter in regards to our late flowering camellias and hellebores. Don’t be tempted to prune out all of the damaged areas yet. Wait until March to see what has recovered.
Bark splitting is another form of cold damage. It is described as loose bark in different areas of the trunk. As the bark defoliates, a canker or a darkened moist area may form. This type of splitting can cause structural damage and may reduce the plant’s ability to transport vital nutrients and water. Several severe cankers can cause plant death.
Preventive measures to reduce cold damage are:
* Select plants that can tolerate cold temperatures and choose a proper site. The north and northwest sides of a home are usually the coldest. Low areas also can harbor cold air.
* Fertilize your plants at the proper time. A plant given the right nutrition is more capable of achieving cold acclimation.
* Prune plants prior to early spring. Pruning in late summer and early fall increases the chance of damage.
* Transplant flowers, shrubs and bushes in early fall. Moving them in the late fall or early winter raises the chance of damage.
* Establish canopies and shade areas for certain plants. The shelter reduces winter dry out and water loss.
* Add windbreaks such as fences, buildings and evergreen trees to reduce injury to ornamentals. Any object breaking winds and freezes can help protect a plant.
* Place container plants in the house, covered patio or garage. They are especially susceptible because their root systems are above ground. Push containers together or wrap them in burlap to decrease heat loss.
* Mulch plants will reduce heat loss of the soil.
* Cover plants with sheets, blankets or boxes, but remove the covering during the day for ventilation. Trapped solar radiation will heat up the environment and cause damage, too.
* Provide sound irrigation to help a healthy plant become cold hardy. Moist soil absorbs more heat, keeping the soil at an elevated temperature.
* Use these tips and keep your plants healthy throughout the winter.
Gardening tip: Remember Valentine’s Day on Feb. 14. Giving a beautiful vase full of fresh flowers or purchasing a potted plant is an excellent gift to give or receive. It is another reason to bring color and beauty into the indoors or outside landscapes.
Wanda Cannon serves as Master Gardener coordinator and horticulture assistant for the UGA Cooperative Extension office in Hall County. Contact her at 770-535-8293 or firstname.lastname@example.org. Her column appears biweekly and on gainesvilletimes.com/life.