Louisiana winters are a welcome departure from the sweltering summer sun and the fleeting warmth of fall. Most years, we can comfortably garden during winter while wearing our summer attire; however, the memories of snow-covered streets (even south of Interstate 10) remain in our minds from last January. While we certainly hope to avoid similar snowfall this year (save for maybe a white Christmas), we can consider ways to protect our gardens as we put a bow on 2025.

As we wade into winter, temperatures drop, and some plants lose the “pop” that they add to the garden. Warm-season annuals may falter at first frost, signaling the conclusion of their lifespan. Tender perennials may die above ground only to resprout with warmer weather. Woody perennials may appear as solely stems, devoid of the foliage and flowers that are featured during spring, summer and fall. How might we protect our plants to set up for a successful spring?

At the Hammond Research Station, several studies seek to solve this issue. Getting to the root of the problem: Cold temperatures have a pronounced effect on plant root systems. A healthy layer of mulch can solve this issue. Recent research has demonstrated that even just 2 inches of pine straw can raise soil temperatures during the cool season, offering a little bit of insulation to get plants through the cold of winter. On a budget? Consider using locally sourced leaf litter (i.e., collect fallen leaves on your property).

While we can’t see the roots, winter damage to aboveground plant parts can be very noticeable. Tractor seat plant (Farfugium) is a low-growing perennial where the large leaves bear resemblance to its namesake. When temperatures drop, the foliage of Farfugium languishes, displaying damage and an unappealing look in the landscape. Fear not, as Farfugium will regrow when you cut out dead foliage and temperatures warm up. Recent research investigating the use of frost fabrics as a cover for sensitive plants has yielded interesting insights to temperature dynamics during the cool-season; however, anecdotal evidence provides a unique look. On the side of the Hammond Station office, plantings of Farfugium were covered with frost fabric or remained exposed to winter’s chill (Figure 1). After the frost passed and plants were uncovered, the difference was quite stark between those exposed to the cold and those protected (Figure 2). While there remains a lot of research to be conducted, early returns are showing that a little bit of coverage during winter can keep plants looking pretty. In any event, a spring pruning allowed the frost-damaged plants to return to their full glory.

Final few tips to keep your garden in good shape for winter:

• Do not cut your ornamental grasses (i.e. muhly grass) back until just before spring starts. This provides an important habitat for wildlife to survive the colder months.
• If you have water features, irrigation lines or anything containing liquid, be very aware of the temperature. You do not want prized features or pipes to become damaged from frozen water expanding.
• Bought a bunch of plants and just haven’t had time to install them yet? Try to heel-in container plants by barricading the container with mulch or soil to offer temporary insulation before spring installation. Pushing pots together tightly can also help the plants insulate each other to get through winter.

Damon Edward Abdi, Ph.D.
Assistant Professor, Extension Specialist, Hammond Research Station

Plants at the Hammond Research Station were covered with frost fabric and left exposed during a winter frost to monitor their response. Photo by Damon Abdi.

Plants covered with frost fabric (foreground) fared better during a frost than those left exposed (background). Photo by Damon Abdi.