LSU AgCenter experts offer cold weather tips

Tobie Blanchard, Reichel, Claudette Hanks

When temperatures dip below freezing, gardeners and homeowners may need to protect their plants and their heating bill.

LSU AgCenter experts have advice to keep shrubs, flowers and vegetables from suffering in the cold and tips to lower your energy bill during cold spells.

LSU AgCenter horticulturists offer these tips for your landscape:

  • To prepare plants for a freeze, thoroughly water them if the soil is dry. This is especially important for container-grown plants, he said. Shrubs in landscape beds also can be helped with irrigation prior to a freeze.
  • Move all tender plants in containers and hanging baskets into buildings where the temperature will stay above freezing. If this is not possible, group container plants in a protected area, like the inside corner of a covered patio, and cover them with plastic.
  • For plants growing in the ground, mulch them with a loose, dry material such as pine straw or leaves.
  • Larger plants can be protected by creating a simple structure and covering it with fabric or plastic. The structure keeps the cover from touching the foliage, preventing broken branches and improving cold protection.
  • For severe freezes when temperatures dip into the teens, providing a heat source under the covering helps. A safe, easy way to do this is to generously wrap or drape the plant with small outdoor Christmas lights. The lights provide heat but do not get hot enough to burn the plant or cover.

LSU AgCenter housing specialist Claudette Reichel said you don’t have to give up comfort to control your heating bill.

Reichel offers these tips:

  • Assess your home. Use the online Energy Star Home Advisor tool to get a prioritized list of energy-saving recommendations customized for your home. If you want to make major improvements in home performance, hire a Residential Energy Services Network (RESNET) or Building Performance Institute (BPI) certified home energy rater or analyst for more precise needs identification and cost-benefit analysis.
  • Optimize your heating system and ductwork. First, change the air filters in forced air systems, as dirty filters reduce efficiency. For safety and efficiency, have the heating system professionally inspected, adjusted and cleaned. Lower your thermostat settings by 5 to 10 degrees when the house is unoccupied and when sleeping to help save money.

If ductwork is in an unconditioned space, like a vented attic, duct leaks and losses can waste large amounts of the heat that you’re paying for. Seal your duct system with mastic — not duct tape, which doesn’t hold over time — on all joints and connections. Caulk gaps between the duct boots and drywall behind the air register grilles. It’s best to have the ductwork professionally leak tested and measured with specialized equipment after sealing to verify effectiveness and find remaining leaks. When replacing ductwork, invest in R-8 insulated ducts and insist on “best practice” layout and installation.

  • Find and seal building air leaks. On a cold day, temporarily turn on exhaust fans to create a suction and find all the cold air leaks in your home. Consumer-priced leak detectors that project colors according to temperature differences can make it easier and faster to find the leaks.

Electric outlet and light switch gaskets are inexpensive and easy to install behind faceplates. Choose durable weather-stripping around doors, windows, and attic access stairs and panels. Use expanding foam sealant around pipe penetrations in walls. If you remove trim around doors and windows to seal gaps, use low expansion foam.

Ceilings (attic floors) often are the largest source of air leakage, especially if your home has recessed can lights that are not ICAT (insulation contact, airtight) rated types. Specialized fire code-compliant covers are available to reduce the leakage, or they can be replaced with ICAT housings. Visit for more information.

A typical fireplace is designed to pull air up and out the chimney — including air you’ve paid to heat — thus increasing cold air leaks and drafts. In fact, using an open-hearth fireplace with your central heating system on can actually increase your heating bill. When using a fireplace for heat, turn off your central heater. When not using the fireplace, make sure the damper is fully closed. If it doesn’t seal tightly, install a chimney balloon.

  • Insulate the water heater tank and pipes. Water heating is typically the second largest part of a home utility bill after cooling and heating. Inexpensive kits and pipe insulation tubes are a simple way to reduce heat loss as well as prevent frozen pipes.
  • Top off attic insulation to R-38. After sealing the attic floor, consider adding more insulation if you have less than R-30, and especially if you have only R-19 or less as is typical in older homes, such as 6-inch thick batts or loose fill.

Reichel said the following bigger jobs may be worthwhile investments in the long run when remodeling and when replacements are needed:

  • Replace an aged, inefficient heating system with an Energy Star-labeled gas furnace or electric heat pump. The Energy Star label means the equipment is more efficient than the minimum but will save you more than the extra first cost.
  • Insulate single-pane windows and wood doors with storm windows and doors, or if old units are in poor condition, replace them with new Energy Star-labeled windows and doors for the climate zone on the label map. When buying window treatments, consider insulated types to increase winter comfort.
  • Insulate raised floors with airtight rigid foam board or closed cell spray foam systems that both insulate and prevent summer moisture problems. Visit the publications page to read “Insulating Raised Floors in a Hot, Humid Climate.”
11/8/2019 9:56:14 PM
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