Now that spring has arrived, your outdoor plants are safe from the harm of frost, right? Unfortunately if you live in certain areas, a hard frost is still possible. (Click here for more details on frost dates in your grow zone.) However, there are easy and inexpensive ways to protect tender plants from the danger of frost.
Protecting plants from the damage of frost is accomplished by trapping the radiant heat from the ground. This can be done by covering the plants, by moving the plants to shelter, or by providing heat to the plants with light bulbs.
To cover up plants: By the time nightfall arrives, much of the heat stored in the garden has been lost. To cover plants, build a frame around the plant or the row of plants in a garden. Use a stake on each side of the plant, then drape newspaper, tarp, or other lightweight sheeting over the posts to create a tent effect.
Alternately, you can lay a protective cover over each plant. This will help to trap in the ambient heat around the plant and slow the loss of heat. Remove covers in the morning once all frost has disappeared to let sunshine and fresh air back in, and to keep the plant from overheating. Burpee offers a floating frost blanket for $14.95 – a 6- by 50-foot lightweight “float” of fabric to place over plants. The blanket traps and collects heat during the day and releases it at night to keep your plants warm and growing.
For small plants, you can use plastic milk jugs, buckets, cardboard boxes or other containers to trap heat. Save milk jugs when you empty them and set them aside in your garden shed or garage to use on evenings when an overnight frost is called for.
For potted plants, either bring them indoors or to a garage. If that’s not possible, wrap the plant with burlap or dig a hole and place the plant and container into the ground.