A cold frame is a simple structure used in gardening to protect plants from cold weather. It typically consists of a transparent top, often made of glass or plastic, that allows sunlight to enter while trapping heat inside. This helps create a warmer microclimate for seedlings and young plants, extending the growing season. Cold frames can be placed directly on the soil or on a raised bed. They are particularly useful for starting vegetable seeds early in the spring or for protecting tender plants during late fall. By using a cold frame, gardeners can enjoy a more productive garden throughout the year.