(02/12/21) BATON ROUGE, La. — An extended cold front has moved into Louisiana. Temperatures will fall below freezing across much of the state this weekend and into next week.
Residents can protect their homes and landscapes with a few steps and items from the hardware or garden store.
Heather Kirk-Ballard, LSU AgCenter consumer horticulturist, said before temperatures drop below freezing, protect tropical and cold-sensitive potted plants.
“You need to get them indoors, in your garage or carport, or protected in the corner of a patio,” she said.
In landscape beds, protect the roots and rhizomes of tropical plants by spreading a 4-to-6-inch layer of mulch around the base of the plant, she said. Heavily mulch cold-sensitive plants, and cover them during the extended periods of below-freezing weather.
Depending on what you have in your vegetable garden, some precautions may need to be taken, said Kiki Fontenot, AgCenter horticulturist.
She said to make sure your garden and potted vegetables are well watered because dried out soils combined with freezing weather is hard on plants.
“If you have cool-season crops out there like carrots, turnips or cabbage — think leafy greens or root crops — they are going to be fine, especially if they are more mature plants,” she said. “These do not need to be covered.”
She said you may see superficial damage such as a purple tinge to broccoli and cauliflower florets.
“On cauliflower, to avoid this, break off a lower leaf and wrap it around the head,” she said.
Cool-season crops such as mustard greens, lettuce and kale that are just now emerging from the soil and are 3 to 4 inches or smaller should be covered.
“Immature plants are not as hardy as mature cool-season plants,” Fontenot said.
She also recommends covering tender crops like blueberries and strawberries. They typically produce in warmer weather, but growers have adapted some production practices to get earlier fruit for the local market.
“If your blueberries and strawberries are blooming, then they need to be covered to protect small fruit and blossoms every time the temperature is predicted to drop below 32 degrees Fahrenheit,” she said. “If your strawberries and blueberries are not fruiting and flowering, they can withstand much cooler temperatures.”
According to Fontenot, strawberry plants often are hardy to the mid-teens, and dormant blueberry shrubs can withstand temperatures as low as single digits.
Fontenot said you can purchase weather protection cloth at a hardware or garden store. Light-colored bedsheets can work, too.
Will Afton, AgCenter horticulture agent, said a common question he gets at his extension office when a freeze approaches is, “When do I need to cover citrus plants?” Afton said a good rule is when the temperatures will stay below 32 degrees for six or more hours, which many areas could see in the next four days.
The cover should extend over the plant and all the way to the ground and should be put out the afternoon before the freeze is expected. Afton said to secure the cover so that it stays in place through the night.
“The sunlight will warm up air inside, and we can trap that air which can keep the temperature in there above freezing,” he said.
Claudette Reichel, LSU AgCenter housing specialist, said during this cold front be sure your home’s water pipes are protected. Steps you can take include:
— Insulate all exposed outdoor and attic pipes with weather-resistant material. Insulating foam tubing designed for pipes is easy to install and inexpensive. Make sure all surfaces of the pipe are covered.
— If an extended and deep freeze is expected, insulation alone may not be sufficient. Consider installing electric heat tape or cable with a built-in thermostat. Be sure the heat tape bears an Underwriters’ Laboratories (UL) seal and is in good condition. Do not overlap the tape when wrapping it around a pipe.
— Use insulating faucet covers, or wrap rags, paper, trash bags or plastic foam around outdoor faucets. Installing pressure-relief valves on outdoor faucets also helps prevent bursting of pipes that freeze.
— Temporarily cover any vents around your home’s foundation.
— Bring water hoses indoors.
— Open the cabinets under the sinks in your kitchen and bathrooms to allow heated indoor air to circulate around water pipes.
— If you normally set back your thermostat at night or when away from home, change the setting to keep some heat on until the severe freeze is over.
— Insulate your outdoor water meter box and be sure its lid is on tight.
— If your home has exposed pipes and a severe freeze is expected, let faucets run at a slow trickle, but don’t run a big stream of water. Too many running faucets in an area can cause drops in community water pressure and problems for firefighters responding to emergencies.
— If you plan to leave town, as some may for the Mardi Gras holiday, consider turning off your water at the shut-off valve while faucets are running to drain your pipes. (Make sure the faucets are turned off before you turn the shut-off valve back on.)
— If you drain your pipes, contact your electric or gas utility for instructions on protecting your water heater.
— Finally, be sure everyone in your household knows where the main water shut-off valve is and check it to make sure it isn’t stuck.
Reichel said if your pipes do freeze, turn off your water at the main shut-off valve. Call a plumber for help.
“Don't use a blowtorch or other flame source, heat lamps or electrical appliances to thaw frozen pipes, she said. “Intense heat could cause steam pressure build-up and an explosion.”
If you try to thaw your own pipes, apply heat slowly, she said, moving it toward the coldest spot on the pipe.
“Never concentrate heat in one spot,” she said. “Cracking ice can shatter a pipe. A relatively safe and effective method is to wrap towels around the frozen section of pipe and pour hot water over them.”
Blueberry bushes used for research at the LSU AgCenter Hill Farm Horticulture Teaching Facilities and University Gardens were covered with weather protection cloth ahead of this week's dip in temperatures. Photo by Kiki Fontenot