Late winter in the Lowcountry is a balancing act, and this year is a sharp reminder of just how unpredictable it can be. The key right now is knowing what to do, what not to do and how to set your garden up for success without reacting too quickly.
Late winter garden preparation is less about action and more about observation. Many plants look rough after a freeze, but appearances can be deceiving. Leaves may be scorched, limp or blackened, especially on tender perennials, citrus and tropical ornamentals. But that doesn’t automatically mean the plant is dead.
Cold-damaged foliage often acts as a buffer, protecting lower buds and stems from additional temperature swings. One of the most common mistakes gardeners make after a cold snap is cutting everything back right away. In most cases, patience is the best tool you have.
Evaluating cold damage takes time. Resist the urge to prune for at least a week or two, sometimes longer, depending on the plant. If you can wait until we’re past the frost-free date in mid-March, even better.
As temperatures moderate, living tissue will begin to reveal itself. Stems that are green and flexible when lightly scratched are still viable. Brown, brittle stems that snap cleanly are likely dead, but even then it’s best to wait until you see where new growth emerges before making final cuts. This is especially important for shrubs like gardenias, hydrangeas and citrus, which often leaf out lower on the plant after cold injury. Pruning too early can remove growth that would have otherwise recovered.
A photo of snapdragon flowers after the cold snap at the Trident Technical College Horticulture Program.
Tony Bertauski/Provided
Many gardeners try to protect plants by covering them before a cold night, and while that can help during a light frost its effectiveness drops sharply once temperatures fall into the low 20s or below. Covers work by trapping heat that radiates up from the soil overnight, but during a hard freeze the soil simply doesn’t have enough stored warmth to protect tender tissue. When cold persists for many hours, the air temperature under the cover eventually matches the surrounding air. Covers may reduce damage slightly, especially near the ground, but they cannot prevent freezing injury in truly cold conditions. This is why even well-covered plants can suffer significant damage during events like the recent cold snap.
There are a few late-winter tasks that are safe and even beneficial right now. Cleaning up fallen branches, removing completely dead annuals, and clearing debris from beds helps reduce pests and disease pressure as the season shifts. If the soil is not waterlogged, you can lightly top-dress beds with compost, allowing nutrients to slowly work in as soil life wakes up. We purchase compost in bulk from All Seasons Landscape Supplies, particularly the mushroom compost and vegetable mix, and have had consistently good results.
Pruning in late winter requires a targeted approach. Most woody plants do not bloom on new growth. Those that do, such as crape myrtles, can be pruned once the worst of the cold has passed, but even then it’s ideal to delay major pruning until mid-March, when the coldest nights are behind us.
For spring-blooming shrubs like azaleas, camellias and many hydrangeas that set buds last year pruning now will remove flowers, so limit yourself to removing only broken or clearly dead wood.
Mulch plays an important role during this transition. It helps moderate soil temperature, reduces freeze-thaw stress and conserves moisture as spring approaches. For plants that were marginally hardy and showed damage, mulch can provide insurance against one last cold night. Just be careful not to bury the trunk or smother new growth when it appears.
A late freeze does not mean the gardening season is ruined. Plants that were stressed may bloom later or less vigorously this year, while others may surprise you with their resilience.
A few years ago, after a couple of cold nights, we had a Meyer lemon and a mandarin tree growing at the horticulture program at Trident Technical College. Both trees shed all of their leaves. The mandarin recovered fully once we moved into March, though it didn’t produce fruit that year because the flower buds were damaged. The Meyer lemon, however, never recovered.
That goes to show cold snaps can have very different outcomes, even among similar plants.
By delaying major pruning, avoiding rushed planting and focusing on soil health and cleanup, you’ll give your garden the best possible chance to rebound from the cold and thrive when true spring finally arrives.
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