Damaging cold weather
Published 9:08 pm Friday, January 19, 2018
My wife and I were welcomed back to Georgia after spending a week in the Caribbean to 32 degrees Fahrenheit this morning. As shocking the cold temperatures are to us, it is equally shocking to the plants in our landscape.
How well will our plants survive this cold weather? It really depends on how cold hardy the trees, shrubs and plants that are in your landscape. If you have a variety of native plants or plants purchased from reputable local garden centers and nurseries, you should be safe. If your plants came from warmer climates such as Florida, California or southern Texas, you may be in trouble.
According to the American Horticulture Society plant hardiness zone map, Troup County may experience low temperatures that range from 5 to 10 degrees Farenheit. Trying to keep a palm tree alive on the back deck is a risky proposition in these temperatures. Hardiness is the ability of a plant to adapt to average minimum and maximum temperatures of a region. With the onset of frosts, plants become more hardened. What disrupts this cycle is a period of warm weather preceding extremely cold weather.
If your plants have been placed in proper locations, their chance of survival increases. If you place shrubs like azaleas and camellias in an understory location protected from the sun and wind they will do well rather than in sunny, exposed locations.
Taking care that the plants have been mulched, watered, fertilized, pruned and sprayed properly during the growing season is very important. Plants have to be in good shape to survive rough, winter conditions.
It may take a while to see the effects of cold damage. What you may see now is bronzing of the foliage a few days after extreme cold. Some plant leaves may turn purple to a sudden chill and that is perfectly normal. Privet, ligustrum and camellia respond this way.
Frozen, dead foliage turns brown. You can try the scratch test with your thumbnail. When you scratch the bark and it is white or green, the wood is still alive. If brown or brittle, the branch has bit the dust.
What can be done right now? Roots are very susceptible to cold damage so make sure that all your plants have a three to five-inch layer of mulch. Mulch acts like insulation and protects the roots from rapid temperature fluctuations.
Wait to prune until March to shape summer-blooming plants and evergreens. Spring blooming plants such as azaleas, spirea and forsythia should be pruned after flowering.
Pruning stimulates new growth which may easily be damaged by cold.
Also, wait until late March or April to fertilize or until the danger of freezing has passed. Like pruning, fertilizer stimulates growth that can be damaged by cold.
Covering tender plants with blankets or sheets may help to reduce frost and cold damage. You may have to prop them up with sticks or poles. This prevents limb breakage. To protect special plants this may work but it may not be practical for all plants. Plastic is also an option but must be removed during sunny or warm days to prevent heat damage.
To prevent thin barked trees from cracking during cold weather, the trunks can be wrapped with materials that can be purchased from local garden centers and nurseries.
What’s going on in Extension?
January 30: Egg Candling Class, no charge, Harris County Extension Office. Call Martha at (706) 628-4824 register. Georgia Department of Ag is teaching the class. Bring valid identification.
If you have any questions or concerns, stop by or call the office.
Brian Maddy is the ANR Agent for Troup County Extension. The Troup County Extension office is located at 144 Sam Walker Drive, LaGrange. 30240 (706) 883-1675. Monday – Friday 8 a.m. to noon and from 1 to 5 p.m.