SDSU Research Highlights Benefits of Soil Tarping

By Scout Nelson

South Dakota State University has released updated recommendations on soil tarping, a practice that can help vegetable growers manage weeds while maintaining soil health. New research shows that tarping can reduce weed pressure and support reduced-tillage farming systems without causing major harm to beneficial soil organisms.

The research was led by SDSU graduate Hannah Voye as part of a multi-state study. Voye worked with Kristine Lang, Assistant Professor and SDSU Extension Consumer Horticulture Specialist, and Rhoda Burrows, retired Professor and SDSU Extension Horticulture Specialist. Their work focused on practical weed management methods that growers can use in vegetable production systems.

The study examined two tarping methods using onions as the test crop at SDSU’s specialty crop field in Brookings. One method used black tarps to block sunlight and prevent weed seeds from germinating. The second method used clear tarps to capture solar heat, encouraging weed seeds to sprout early and reduce the number of weeds later in the season.

Researchers found that soil tarping helped lower weed pressure while causing very limited effects on soil microbes when used for two to six weeks. Because South Dakota often experiences cool spring conditions, Voye and Lang recommend using black or clear tarps for at least six weeks to achieve effective results.

“Many growers were worried about hurting soil microbes on their farms, and this research showed that impacts on soil microbes were very minimal when tarping for 2 to 6 weeks,” Lang said. “If farmers start tarping for months at a time that story may change, but I think this shows that there is a balance that can be found between managing weeds and holding onto soil health.”

The findings were published in two research papers focused on reduced-tillage vegetable production and soil health. Voye hopes the results encourage more research and provide useful information for growers looking for new weed management options.

For more information on horticulture research, visit the SDSU Extension Horticulture Research page or contact Kristine Lang, assistant professor and SDSU Extension Consumer Horticulture Specialist.

Photo Credit: gettyimages-zoran-zeremski