OFFICE OF MONTGOMERY COUNTY
9020 Airport Rd
Conroe, TX 77303
(936) 539-7822 phone
(936) 788-8394 fax
mpotter@ag.tamu.edu
NEWS RELEASE
BY MICHAEL W. POTTER
County Extension Agent – Horticulture
February 12, 2021
Gardening has plenty of challenges. We have to battle insects, diseases, drought, wind, excessive rainfall, soil problems, lack of pollination, too much sun, not enough sun, blazing heat, bitter cold…and the list goes on! With freezing temperatures upon us, there are a few things we can do to help get our plants through this time.
We all know that freezes can kill plants. It is how it happens that we need to somewhat understand. When the water inside a plant freezes it causes ice crystals to form that pierce the cell walls of the plant. When the temperature warms up, the cells leak out their fluids as they die and turn to mush. Basically, the cells burst. Freeze damage first shows up as dark, water-soaked tissues which then turns black to brown.
Sometimes all we need to do is keep a plant alive through the cold. The first parts of most plants
to freeze are tender new growth areas and the areas between leaf veins where the leaf is thinnest. A little injury to new growth is tolerable especially if the plant itself is saved. Keep in mind also that plants vary in their cold hardiness as they develop from seedlings to mature producing plants. Broccoli for example is quite hardy as a strong, growing plant but the flower buds, the part we eat, are much more sensitive to cold.
So where do we start. First, watering your plants right before a freeze creates a source of warmth that will slow heat loss. This alone is not going to provide protection from a hard freeze but can be used with covers to make a small difference on a marginal night.
Covering plants is the simplest, most practical way to protect against a frost or freeze. Gardeners
head out with sheets, blankets, rowcovers and anything else that they can get their hands on to wrap up plants for a cold night. Just keep in mind that plastics can trap heat, however a plastic material will be just as cold on the inside of the material as it is on the outside. So plastic is not necessarily the best choice. The main source of heat for a plant is the soil. On a cold night heat from the soil rises up around the plants. If you use a blanket to trap this heat within the plant’s canopy you can make a very significant difference on a cold night. To cover plants effectively, lay the cover over the plant and allow it to drape down to the soil on all sides. Then secure it with boards, bricks, rocks or soil to hold in the air. This is especially helpful in preventing a breeze from cooling things down faster. The next day, remove the covers to allow the sun to warm the soil surface a little and then replace the covers as the sun goes down. Spunbound polyester rowcover fabric works well to hold in heat. The lighter weight types are not as effective as the heavier types, which are generally sold as “frost blankets”, but all types are beneficial. Also, some people use Christmas lights. LED lights do not emit enough heat, so use the old fashioned ones. You can wrap the plants and use covers. Just make sure they are safely used as to not start a fire.
Consider moving container plants indoors or into a garage for protection. You can also place the, if you have more that a few, close together and cover them collectively. Piling up mulch around tender perennials can also be used, however make sure it is removed after the freeze dispates. I know we are all taken back by this sudden change in weather.. but… IT IS WHAT IS IS…. Just remember protect you pipes, irrigation systems, your pets and yourself.
Don’t forget to send your garden questions to Plant Answers at 9020 Airport Rd., Conroe TX 77303 or e-mail me at mpotter@ag.tamu.edu.
For additional information on protecting your landscape check our website www.mcmga.com
Educational programs of the Texas AgriLife Extension Service are open to all people without regard to race, color, sex, disability, religion, age, or national origin.
The Texas A&M University System, U.S. Department of Agriculture, and the County Commissioners Courts of Texas Cooperating