Prioritize the most at-risk plants before frost develops:

• Most annuals: Petunias, zinnias, nasturtiums, and many others
• Some vegetables: Tomatoes, peppers, spinach, eggplant, and others
• Some tropicals: Dahlias, hibiscus, angel’s trumpets, fruit trees, and more

Overwinter delicate plants by moving them indoors. Plants already in containers can be moved intact to a sunroom or other suitable place in the home. It's also possible to move plant specimens:

• Trim the plant: Cut back the plant by one-third.
• Transplant the plant: Move the plant and its root ball to a container filled with potting soil.
• Acclimate the plant: Alternate the plant in and out of the house, one week at a time.
• Check for pests: Before moving, check the plant for mites and insects, and remove them.
• Move the plant: Move the plant indoors for the winter before freezing weather develops.

Protect plant roots by adding a thick layer of mulch around the base. Like a blanket, mulch insulates the soil and keeps temperatures stable.

The best time to apply mulch to the plants is in late fall. For frost-proofing, you can use either organic or inorganic mulch:

Organic mulch: Organic mulch, made from living things, includes grass clippings, leaves, and wood, among others. Organic mulch both insulates and adds nutrients to the soil.

Inorganic mulch: Inorganic mulch is made from rubber chips, plastic, rocks, and other synthetic or mineral elements. Inorganic mulch will insulate the roots against frost but will not add nutrients.

Covering plants can help hold in the heat and prevent frost from developing.

Frost cloths made from fabric-like synthetics are lightweight enough to be placed directly on top of the plants. The cloths trap heat but allow sun and air to flow through.

Instead of frost cloths, you can use old sheets, blankets, or towels. Since they're heavier than frost cloths, they should be elevated from the plant. Use wooden stakes, saw horses, pipes, wire loops, tomato cages, or anything available to prevent the cloth from touching the plant.

If your plants frequently succumb to frost damage, it may be time to consider shifting your garden toward more frost-hardy shrubs and herbs, vegetables, and winter flowers.

Phase out or reduce the number of plants easily damaged by frost. This also helps reduce the number of gardening tasks you need to do before winter.

Irrigate the soil around your frost-sensitive plants soon before a frost arrives. Moist soil retains more heat than dry soil.

Deeply watered soil is dense and has sufficient mass to retain more heat than dry soil. The irrigated soil acts as a soil heat bank to slowly return the heat to the plants during the frost.