The New Year has brought Liberty County and the surrounding areas some of the lowest temperatures in years, making life miserable for people, pets, livestock and plants.
Understandably, area gardeners are now asking how much plant injury they can expect as a result of these hard freezes.
The answer to this question depends largely upon your response to the following three question:
Are the trees, shrubs and perennial plants in your landscape cold hardy? That is, are these plants suited to our local weather conditions and our particular climate zone?
Liberty County is located in USDA Plant Hardiness Zone 8b, which means that our winter temperatures can generally fall to 15 to 20 degrees F. Plants purchased locally from reputable garden centers and nurseries should be hardy here.
On the other hand, plants that you buy, transplant or receive as gifts that are adapted to warmer climates of Florida, southern Texas or California may be tender here, and therefore less able to survive our colder winters, at least not without a little help.
Have your plants been properly located and planted in the yard? For example, some shrubs, like azaleas and camellias, suffer from cold injury when placed in sunny, open exposures. Always place these plants where they will receive adequate protection from too much winter sun and wind.
If possible, locate citrus plants in a protected area, such as near a home or some other structure, preferably on the south side. This type of location provides maximum protection from severe freezes, as the wind associated with South Georgia cold weather generally comes from the north to northwest.
All plants have certain environmental requirements, so keep them in mind when planting.
Did I take good care of my ornamentals throughout the growing season? If you answered yes, then that means that your plants were properly watered, mulched, fertilized and pruned to maintain optimum vigor and growth throughout the growing season.
Weak, unhealthy or poorly-maintained plants are usually the first to suffer during periods of extremely cold weather.
It is difficult to ascertain cold damage a day or even a week after a severe freeze. In most cases, it may be spring before you can really evaluate exactly how much damage has really occurred. It is when your plants begin, or fail, to leaf out or flower in the spring that the extent of winter injury becomes obvious.
What you may see now, just a few days to weeks after extremely cold weather, is a bronzing of the foliage. This is especially true of certain azaleas and boxwoods. Foliage of privet, ligustrum and camellia often turns purple after very cold weather. This discoloration is simply the plant’s response to a sudden chill and is perfectly normal. The foliage is alive, just a bit cold from the low temperatures.
On the other hand, frozen or dead foliage almost always turns brown. In many cases, leaves will curl, roll up or drop from the stems. By simply using your fingernail to scratch the bark you can determine if a branch is dead or alive.
If the stem tissue is green or white where you scratch, then that wood is still alive and should put out new growth in the spring. If the stem tissue is brown or brittle where you have scratched, then that branch is dead and the wood should be removed in the early spring after freezing weather has passed.
Azaleas, camellias, gardenias and hydrangeas and other plants often experience some bark splitting as a result of extremely cold weather. You can see this damage on lower stems and branches near the soil surface. Injury from split bark appears later in the year as dead twigs and branches.
So now you know what to look for, but you may be wondering what you can do now. If your shrubs and trees have been properly cared for, then they should come through this winter with little or no problems.
But do keep these tips in mind in order to lessen or prevent further damage this year, especially if you have cold sensitive plants in your yard:
• Maintain a 3- to 5-inch layer of mulch around plants at all times. If your mulch level falls below this, then add some more. Mulch helps to insulate root systems much like fiberglass helps to insulate your home from cold weather. Mulch also helps to protect the soil from rapid temperature fluctuations, which are a primary cause of cold damage.
• Drop those pruners. Pruning right before or after freezing temperatures can cause additional damage to your plants. For now, the best thing you can do is wait. Depending on the conditions, generally waiting until late February or March is fine for shaping most evergreens and summer-blooming plants. Remember to prune spring-blooming plants, such as azaleas, forsythia and spirea, after flowering.
• Do not fertilize. Fertilizing now, like pruning, may stimulate a growth flush that future cold conditions would likely injure or kill. Delay fertilizing until late March or April when all danger of freezing has passed.
• Cover tender plants with freeze cloth, old quilts, blankets or sheets to help reduce frost and cold damage. This technique may not be practical for all plants, but it can be used to protect perhaps a special shrub, small fruit trees, semi-hardy plants, etc. It may be necessary to use sticks or poles to prop up blankets, quilts or other heavy covering to prevent branches or limbs from breaking. Plastic can also be used as a nighttime cover, but be sure to take it off on sunny or warm days to prevent heat damage to your plants. If you choose to use plastic, be sure to put a sheet between it and your plant.
• Wrap the trunks of young or thin-barked trees with freeze cloth, burlap or other tree wrapping materials to prevent cracks from developing. Protecting the graft union on your young fruit trees is especially important. Local garden centers and nurseries can usually supply you with tree wrap.
For more information on cold damage and caring for your plants, contact the Liberty County Extension office at 912-876-2133 or firstname.lastname@example.org.