How does a Cold Frame protect plants from frost

A cold frame is a simple gardening structure used to extend the growing season for plants in early spring and late fall, and to protect plants in winter. It consists of a transparent cover and surrounding walls, the cover is made of transparent materials such as plastic or polycarbonate, which can effectively capture and retain heat during the day. At night, the cover and surrounding walls can slow down the loss of heat, gradually release the heat accumulated during the day, and keep the internal temperature relatively stable, thus reducing the damage of frost to plants.

The structural design of the cold frame also effectively isolates cold air. The walls and cover isolate the plants from the cold air outside, forming a relatively closed warm space. Through this physical isolation, the cold frame can significantly reduce the time and extent to which plants are exposed to cold air, reducing the risk of frost. The grounded cold frame utilizes the ground as a heat source, as the ground temperature is usually higher than the air temperature. This design helps to reduce heat loss and further maintain the internal temperature.

The design of the cold frame allows them to be easily opened for proper ventilation. When the temperature rises gradually, proper ventilation of the cold frame can prevent the internal temperature from being too high and the humidity from being too high. Excessive temperature and humidity can lead to plant diseases. Timely ventilation can maintain good air circulation and promote healthy plant growth.