May - A 2007 View On Greenhouse Production

By Merle H. Jensen

WITH the advent of plastics in agriculture, the early work by professor Emmert (often considered the father of agricultural plastics) developed many principles in the use of polyethylene for greenhouses in place of more expensive glass. His work set the stage, worldwide, to revolutionize the greenhouse vegetable industry. Low wooden structures have given way to high-tech, taller, metal structures, to achieve a more uniform growing environment. Wide sheets of polyethylene are tailored to retard heat loss and allow entry of low levels of UV light to retard insects that are vectors of many serious virus diseases.

Today’s greenhouses are now better understood as “controlled environment agriculture” with precise control over air and root temperatures, water, humidity, plant nutrition, carbon dioxide, and even light.

Often termed plant factories, today’s greenhouses are highly automated with the artificial environment and growing system under nearly total computer control. Due to polyethylene and other plastic products, greenhouse technology is changing rapidly with systems producing yields and quality never before realized, and a future never more positive.

Jensen is professor emeritus, plant sciences, University of Arizona;
smjensen1@earthlink.net