Preparing Plants for Freezing Temps

Here in southern Mississippi, we are forecasted to have our first big, several day long, cold snap with temperatures getting into the 20s at night. We may even get a little freezing precipitation. With this in mind lets discuss how to prepare your garden for these cold conditions.

Water Needs Before and After

Watering your plants before a freeze can help protect them from cold injury. Soil that is well watered absorbs more heat helping increase the elevated temperature around the plant.

Check the water needs of plants after a freeze. After very cold temperatures, water that is in the soil may still be frozen and unavailable to the roots. If plants are transpiring (losing water from their leaves) and water is unavailable to the roots, plants may dry out. To provide water for plants, apply water to thaw the soil and the ice.

Mulch

Poorly drained soils result in plants that have weak and shallow roots, which are more susceptible to cold injury. Apply a 3-4 inch layer of mulch around plants to insulate roots and retain moisture. Mulch can also help prevent roots from being pushed out of the soil during hard freezes.

Cover and Heating

Bring potted plants and hanging baskets indoors when a frost is expected. Plants in containers are more susceptible to frost damage because they don’t benefit from the insulating powers of the earth. Roots that sustain damage from cold temperatures may not show immediate signs of damage, but these plants will show signs of stress when temperatures rise.

For containers that cannot be moved inside, add mulch to the container and cover the plant to decrease heat loss from the top. Wrap the bases of the containers in plastic, burlap, or blankets to reduce heat loss from the bottom.

Plants that grow close to the ground are usually protected from heat radiating from the soil. Plants that are tall and more open do not receive this radiating heat and are not as protected from the cold.

Cover plants with a cloth, blanket, or sheet to protect them from a light frost. Do not use plastic, as it can damage plants. Covers need to reach the ground or be tied off to form a layer of insulation from the cold temperatures. To prevent foliage breakage, avoid having the covers (sheets, blankets) touch the foliage. Remember to remove protective coverings from the plant canopy after cold temperatures have passed.