Across the South, we all dealt with the crazy flash freeze just before Christmas 2022. Within just eight hours, temperatures plummeted 50 degrees to subzero levels. Homeowners all over the region are still dealing with the effects from this Arctic blast.
A polar vortex is a large area of low pressure and cold air surrounding both of the earth’s poles. The vortex gets stronger in the winter and the air surrounding the North Pole sometimes gets pushed south, resulting in extreme cold snaps for Northern America, like the one we had last winter and in February of 2021. The arrival of this Arctic air causes temperatures to plunge rapidly, wreaking havoc on our greenery.
When a plant freezes, the water-filled cells of the plant freeze, causing the cells to expand and rupture. Typically, trees and shrubs gradually pull the majority of the water flowing through its cells back to their roots in preparation for a freeze. When there is a rapid plunge in temperatures they do not have enough time and, if the mercury drop is severe enough, all of the fluid in the trees or shrubs will freeze.
That is exactly what happened to our green friends on the Thursday before Christmas of 2022. Middle Tennessee saw temperatures of approximately 50° F drop to below 0° F in just eight hours. Trees and shrubs didn’t have the time they needed to pull back the water in the cells, causing death to branches and, in many cases, entire trees and plants.
Photos by Ashleigh Newnes
At the beginning of the year it was hard to tell which plants had actually survived and which had bit the dust. In recent weeks, the signs of damage or survival have become more apparent. Many homeowners are surprised by the green growth on their shrubs and trees while some have a lot of dead limbs that need to be cut away. Some, sadly, lost their shrubs altogether.
If you are still unsure if your tree or its branches are dead, you can do the scratch test. Using your fingernail or a knife, scratch the surface of the bark. If it is green—it’s still alive! If you scratch the outer limbs and they aren’t green but the inner trunk is, then you should cut away the dead branches and work your way toward the new growth.
Unfortunately, there is not much preparation that can be made for an event such as a polar vortex or a flash freeze this severe. Even choosing plants rated for our USDA zone won’t guarantee survival or an escape from damage. Mother Nature calls the shots—sometimes it’s just out of our control.
