Abstract: This disclosure is of a controlled environment agriculture facility in which a plurality of plant grow support racks are structured and arranged within a plant grow enclosure to define an air return passage from the enclosure with air ingress to such passage being distributed over surfaces of the racks. This provides good uniformity of air distribution within the enclosure and affords improved transportability and installation of the facility.

Abstract: This disclosure is of a controlled environment agriculture system in which a plurality of plant grow support racks are arranged in an array complementary to that of the lamps which provide illumination for the grow racks, so as to provide two positions for the rack array in each of which positions alternate racks are fully illuminated and the others not. The lamps then may be operated continuously and the rack array shifted between these two positions to provide alternating periods of full illumination and relative darkness for each rack. Means also are provided for improving the uniformity of air distribution to all racks within the array, and for control of humidity within the system by adjustment of the rate of moisture removal by the air conditioners to balance that of moisture addition through plant transpiration.