Improve Vegetable System Weed Management with Tarping

By Alaina Friesleben and Ajay Nair

Managing weeds is one of the greatest challenges for vegetable growers, accounting for significant yield loss each year. While cultivation and herbicide use can combat weed growth, over time, these methods can cause soil erosion issues and human health concerns.

A new resource from Iowa State University Extension and Outreach offers guidance on an excellent weed management alternative: tarping.

“Tarping to Improve Weed Management and Reduce Tillage in Vegetable Systems” outlines methods of tarping use and provides information on tarp implementation and installation.

Publication co-author and graduate research assistant in the ISU Department of Horticulture, Carly Strauser, noted its benefits.

“Tarps can provide many of the same functions tillage does, such as killing weeds or decomposing cover crops, making it great for no-till systems. They are a great investment for growers and are relatively inexpensive because they are multifunctional and can be used for multiple years,” she said.

The resource also demonstrates the effectiveness of two tarping processes: occulation and solarization.

Occulation aims to kill weeds by blocking access to sunlight with a black and white tarp, which prevents weeds from photosynthesizing. Solarization uses a clear tarp to create a warm environment, killing weeds due to excess heat.

Ajay Nair, professor and chair of the Department of Horticulture at Iowa State University, shared the findings of the study in the resource.

“Spring temperatures in the north central United States are typically not warm enough to terminate weeds via solarization,” he said. “Clear tarp treatments and no-tarp control treatments required cultivation to terminate weeds prior to planting the cash crop, whereas black and white tarps did not.”

The four-page publication is available for download through the ISU Extension Store.