LEXINGTON, Ky. — Diversification continues to be an important part of organic agriculture. Organic growers’ commitment to this practice opens new doors to markets, acts as a safeguard against risks, promotes biodiversity and fosters the growth of robust local communities and economies. However, organic diversification comes with its own set of challenges.  

University of Kentucky Martin-Gatton College of Agriculture, Food and Environment researchers aim to bring predictability to the organic market thanks to a $3.5 million grant from the U.S. Department of Agriculture’s Organic Agriculture Research and Extension Initiative (OREI) program.  

Alongside UK researchers Ric Bessin and Mark Williams, David Gonthier is working with lead scientists and extension specialists from Cornell University, Iowa State University and The Organic Center on a four-year project entitled “Expanding Resilient Climate and Pest Protection Systems for Diversified Organic Specialty Crop Producers.” The endeavor highlights mesotunnels as a potential dual solution to pest and climate challenges.  

 There are basically three tunnel types growers might use to create some sort of protective barrier between crops and the environment. “Meso” means “middle,” so mesotunnels are medium-size tunnels – taller than low tunnels and shorter than high tunnels. But mesotunnels fit into a niche that’s different from either of the other types.

 “Mesotunnels are essentially row covers made of nylon fine-mesh nets, supported by tall hoops, designed to serve as an effective barrier against insect pests and insect-transmitted diseases,” said Gonthier, an assistant professor in the University of Kentucky Department of Entomology. “These are durable, breathable and light-permeable mesh nets that may also protect against some adverse weather conditions.”

This effort is backed by a $3.5 million grant from the U.S. Department of Agriculture’s Organic Agriculture Research and Extension Initiative (OREI) program.

 “The main objective is to address the challenges organic farmers face while cultivating fruits and vegetables in the nation’s Southeast, Midwest and Northeast regions,” Gonthier said. “The research involves conducting field experiments and on-farm mesotunnel trials with a wide range of crops, including broccoli and cabbage, squash, melons and eggplant.”

According to Gonthier, if tunnel types were cousins, mesotunnels would be first cousins to low tunnels and maybe third cousins to high tunnels. Mesotunnels and low tunnels are similar in that they are set up and taken down in the same growing season. High tunnels are long-term structures that stay in the same place year after year.

Mesotunnels are taller than low tunnels and their covering is different. A breathable nylon-mesh fabric is used, one that resembles window screen. Their larger scale and more breathable covering (which prevents overheating even in mid-summer) means that mesotunnels can potentially be used throughout the growing season. Low tunnels have to be removed when flowering starts in order to avoid overheating and overcrowding the plants.

 “This project does not merely stop at identifying the potential of mesotunnels,” said Kathleen Fiske, a doctoral student working on the project. “It also delves into innovative strategies to seamlessly integrate mesotunnels into diversified organic fruit and vegetable rotations. The goal is to understand how mesotunnels can enhance crop protection and how they can strategically employ them to maximize grower profits.”

The research will also address how growers perceive mesotunnels relative to other protection strategies, including pesticide use.

 “While mesotunnels reduce insecticide use, they are made of plastic and there is growing concern surrounding plastic use in our food system from the field to the grocery store,” Gonthier said. “Grower, consumer and industry perceptions of pesticide use, plastic and many other factors may shape future adoption, depending on how mesotunnels fit into the narrative.”

Gonthier said a well-structured regional and national outreach program will ensure that project knowledge and insights reach a broad audience. By highlighting the most promising protection systems, researchers hope to empower thousands of growers and educate millions of consumers about the benefits of mesotunnels along with the sustainability role in the organic specialty crop industry.

“Organic farming is notoriously challenging in the Southeast United States and those challenges become a moving target with ever-increasing extreme weather events associated with climate change,” said Amber Sciligo, director of science programs at The Organic Center. “We are very excited that this work research will offer more effective tools for organic pest management and weather protection for farms of various sizes, from the backyard garden to commercial fields.”