One of the main concerns of gardeners and homeowners is the threat of freezing weather or frost, which can kill plants. Depending on how sensitive the plants are, there are ways to protect them through a cold season. In some instances, all it takes is a little amount of extra caring for the plants to help them get through winter.
Freeze versus Frost
Freeze occurs when the temperature drops below the freezing point. When the water freezes inside a plant, it can cause irreparable damage to the plant cells. Plants have different reactions to freezing temperatures.
Annual, frost-tender and tropical plants cannot survive in freezing temperatures. Tropical only survive in warm weather while annuals are able to disperse seeds, which replenish their numbers when the weather becomes suitable.
The foliage of root-hardy perennials become frozen but the roots survive and stay dormant until spring comes.
Shrubs, trees and full hardy perennials become dormant, reduce sap content and conserve water. By doing so, they become less vulnerable to freezing. Early foliage that blooms in spring sometimes get damaged when there are late spring freezes, but the plants are usually able to recover.
Separately, frost occurs on clear nights. When the temperature is close to freezing, ice crystals form on the surface of the plant just as dew forms on warmer nights.
With the exception of the most sensitive plants, the effect of frost varies depending on how cold it gets and how long the cold lasts.
Light frost harms only the most sensitive plants. Hard frost damages foliage but the roots may survive. Severe freeze cause plants to die from drying too much.
Protect Your Plants
Choose your plants wisely depending on the climate where you live. As the season grows cold, watch weather reports for frost warnings in your area.
Small plants may be brought indoors and supplied with artificial warmth while trees and shrubs may be covered with a blanket or burlap to protect it from too much cold. Also water plants thoroughly before a freeze because it keeps them hydrated and prevents desiccation. For small plants that cannot be brought indoors, a layer of mulch can be used to cover them.