Coldframe Microclimates under Solid and Perforated Plastic Covers

摘要

Microclimatic variables were measured in three plant beds covered with materials having 1/4 in. perforations on a 3-in. square pattern and in one plant bed covered with nonperforated clear polyethylene plastic. One of the perforated covers was clear polyethylene plastic, one was a lamination of white cloth and polyethylene plastic, and the third was a laminatyellow cloth and polyethylene plastic. Data are presented to show how the microclimate parameters of a coldframe covered with a nonperforated clear plastic film were modified when the cover had perforations, or perforations and cloth laminations. Emphasis is given to the modification of the temperature regime, especially on clear warm days when temperatures in conventional coldframes covered with nonperforated plastic film tend to become excessive for tender plants. (Author)