Controlled Environment Agriculture

Our Best Practices

Modified Environment Agriculture

demonstration greenhouse

Modified Environment Agriculture (MEA) has been popular on and off over the last hundred years and is currently experiencing a resurgence of popularity recently in the form of high tunnels. MEA refers to any structure that protects a crop from the elements. While this could technically apply to row covers, we will limit our discussion on this website to those structures that are covered at least in plastic and are semi-permanent.

The most popular MEA structures are hoop houses and high tunnels. Both are intended for season extension and not year-round growth. There is a dramatic range in equipment usage for these structures. For the most basic case, the plastic sides are rolled up for ventilation and there is no electricity to the structure - so no fans, heat, supplemental light. At the other extreme, there are high tunnels where there are fans for ventilation, electricity, supplemental light, and supplemental heat.

Links to pages about High Tunnels:

A USDA sponsored project involving Kansas State Research and Extension, University of Missouri Extension and University of Nebraska Cooperative Extension.

The Pennsylvania State (Penn State) Center for plasticulture, established in 1998. This page includes reports on the research done at this facility as well as some general information about high tunnels. There is also a link to the 2003 production guide, a publication that echos some of the information on the website and describes some research in more detail.

View the 2003 High Tunnel Production Manual
Penn State Center for Plasticulture.

This page from Rutgers University provides links to research results in the form of final reports for the projects conducted in 6 high tunnels spread over 2 locations.