Greenhouse IPM

Greenhouse production in Pennsylvania is a diverse enterprise. Greenhouse businesses range from small family run operations to very large greenhouse operations that have several acres under glass or plastic. Moreover, both food and non-food crops are produced in greenhouses in the state. The non-food production is part of the green industry. Food crop production primarily consists of the production of vegetables and herbs.

A semi-permanent type of greenhouse, high tunnels, have been becoming quite popular in the state recently. To learn more about high tunnels visit the plasticulture web site.

PA IPM has devoted a great deal of effort to designing IPM solutions for greenhouse production, particularly biological control. Biological control is the use of one organism against another organism. For instance, a tiny parasitoid wasp may be released to control white flies on greenhouse grown tomato plants.

PA IPM also has ongoing education programs in central and western Pennsylvania. Read on to learn more about greenhouse IPM in Pennsylvania.

PA IPM Greenhouse Education Program

The greenhouse IPM branch of PA IPM is currently active in central Pennsylvania, Lancaster and Pittsburgh areas. Cathy Thomas, a biocontrol specialist based at the PA Department of Agriculture, has headed this program for the last ten years working in many regions throughout the state with special focus in central and southwestern PA. Thomas has been a part of numerous IPM/biocontrol related projects working with Penn State and Pennsylvania Department of Agriculture personnel. She has compiled her biocontrol advice into a sixty-six page full color publication"Bug vs. Bug" and is collaborating on the "Greenhouse IPM Manual with an Emphasis on "Biocontrol" soon to be released.

A greenhouse IPM program follows a biointensive strategy and relies upon sanitation, mechanical barriers, biocontrol, scouting, and targeted pesticides when necessary. According to Thomas, IPM is catching on because many growers are looking for viable alternatives to using pesticides.

Lancaster Area

This project is in its third year and is headed by Cathy Thomas. A local adult farmer advisor, Jeff Stoltzfus, acts as a liaison with the Amish and Mennonite community, making it easier for the program to be a success. The education program, funded by the Environmental Protection Agency and Sustainable Agriculture Research and Education program, focuses on the Amish and Mennonite community, but is open to any grower in Lancaster County or surrounding counties with an interest in reducing pesticide use.

The number of greenhouse growers in this area will likely increase because many farmers are shifting to greenhouse production as a minor crop to replace or supplement income lost from tobacco production and low market prices. It is also a popular choice among Amish and Mennonite growers because a greenhouse operation doesn't require much space and farmland is becoming harder to obtain.

Thomas gives hands-on training to the growers, who are in many cases new to the greenhouse industry and have no prior knowledge of pesticides or IPM methods. Thomas says that when she first started the program, some of the growers were using the same pesticide compounds in the greenhouses that they were using in their fields. This can be a dangerous situation, since the compounds used in fields are not the same as those used in greenhouses. They are much more toxic, and sometimes don't even target common greenhouse pests.

Thomas is showing growers how a successful IPM/biocontrol system can replace traditional pesticides. Through use of biologically compatible pesticides combined with biological controls, growers can slow resistance in target pests, create a safer working environment for the family, and maintain quality crops while increasing profitability when marketed as "pesticide free."

Pittsburgh Area

Greenhouse growers in Southwestern Pennsylvania are aiming to reduce their use of pesticides through a recently expanded IPM training program. This project is funded by the Environmental Protection Agency and Sustainable Agriculture Research and Education program.

The project includes a diverse group consisting of bedding plant and greenhouse vegetable growers that have been underserved in the past due to limited resources. Ten growers are participating and Les Garrett, a former plant inspector of 33 years with the Pennsylvania Department of Agriculture, has been hired as an IPM consultant to assist with the program.

Garret makes weekly visits to the ten growers spanning Allegheny, Armstrong, Indiana and Westmoreland Counties and trains growers on greenhouse IPM methods such as, pest scouting techniques, life cycles of the pests and biocontrol agents. Garrett comments that he shows the grower how biocontrol alternatives can be used and blended with compatible chemical controls to manage pests.

While it's still early in the program, many of the growers are already seeing the benefits of an IPM program. Garrett will work with the growers through a crop cycle so the growers gain confidence and independence. According to Thomas, by converting these growers to IPM methods they expect to see a reduction of pesticide use by at least 50 percent, thereby slowing resistance in target pests and creating a safer working environment.

Contact Information

For questions about the greenhouse IPM program contact:

Cathy Thomas
PA Dept. of Agriculture
Bureau of Plant Industry
2301 North Cameron Street
Harrisburg, PA 17110-9408
Phone:(717) 705-5857 x254
Email:caththomas@state.pa.us