Cold Weather Tips
Which Plants Need Protection?
It's inevitable...spring in our region gives us periods of warm weather followed by snaps of cold temperatures that can damage those plants that were fooled by the early warmth.
Tender plants, immature plants, new growth and blooms need the most protection. Here's a list of some plants you should protect from frost in late February to March:
- Tropicals: should be treated like houseplants during winter in our region
- Most annuals: Some annuals, like pansies & violas, will tolerate cold and freeze easily
- Tender sprouts: Bulbs or perennials that have sprouted, like daffodils, will need protection
- Trees and shrubs with blooms, flower buds, and/or new growth: These plants will weather the freeze just fine, but blooms and new growth may be damaged if not protected & you'll have to cut it back to let the plant recover. Some flowering trees may be too large to cover - focus on your smaller trees or newly planted trees.
- Plants that have new growth or buds at this time of year can include:
- Cherry, dogwood, redbud trees
- Azaleas, forsythia, loropetalums, pieris, rhododendrons, roses
- Blueberries and strawberries
- Tomatoes, peppers, cucumbers, etc.
- Boston, Kimberly Queen & Macho ferns
- Begonias, marigolds, and petunias
How Do I Protect Them?
- Cover: Place a frost cloth over the plants prior to sunset before the frost to help trap in the warmth from the soil and protect them from the wind. Ideally, frost cloth should not touch the foliage. Secure the frost cloth with stakes, rocks or bricks so the wind doesn't blow it away. It's important that you remove the frost cloth first thing in the morning so that the cloth does not trap in the heat from the sun and cause damage. For small sprouted plants, empty buckets or empty planting containers will suffice for coverage.
- Water: Water your trees and shrubs prior to sunset before the frost. The added moisture helps hold heat in the soil so the plants' roots can better tolerate the cold. Be sure to water the SOIL, not the leaves or stems. For annuals, perennials, herbs, and veggies leave them dry; they tend to handle extreme cold better if they are drier.
- Move your potted plants & hanging baskets indoors or to a protected area like a garage or shed.
- Mulch: Mulching your garden insulates the plants' roots and retains soil moisture, which helps regulate ground temperatures during a freeze. Your garden should have a 2-3 inch layer of mulch.
- Wash: Any plants that you can't cover to protect from frost can be washed at sunrise AFTER the cold snap. Use a hose to gently spray them with water BEFORE the sun comes out. This will help minimize frost damage by melting the ice as quickly as possible.
Which Plants Tolerate Our Climate?
The easiest way to know what grows best in our region is to know your hardiness zone according to the USDA Plant Hardiness Map (7b and 8a in the Atlanta and Charlotte areas). Then check the plant's information tag when purchasing. Plants that thrive in the northern hardiness zones can weather a freeze/frost more easily. If you've planted spring and summer plants that usually thrive better in more southern zones, then those will be the ones that need protection more than others during a freeze (mostly annuals).
Assessing Cold Damage
- Be patient: You can't tell the extent of the cold damage until a plant starts actively leafing out/growing in spring.
- Be on the lookout: Watch for signs of new growth throughout the plant. Depending on the plant, you may not see leafing out until April.
- Try the Scratch Test: Another way to see if a plant will spring back to life is to lightly scratch the bark and look for fresh, lighter-colored wood. If you scratch the branch and the color is the same without any sap, then it is likely dead from the damage.
Treating Cold Damaged Plants
- Fertilize: Once a plant starts leafing out, start a fertilizing program with an all-purpose fertilizer to improve root health.
- Prune: If you had branches that broke during the icy weather, prune them so they have a clean-cut to heal properly.