ISU Offers Weed Control Guide with Tarping Techniques

By Andi Anderson

Iowa State University (ISU) Extension and Outreach has released a new publication aimed at helping vegetable growers improve weed management while protecting soil health.

The guide, titled “Tarping to Improve Weed Management and Reduce Tillage in Vegetable Systems,” introduces effective tarping techniques to reduce reliance on herbicides and tillage.

Weed management is a major concern for vegetable farmers, with traditional methods like tillage and chemical herbicides often leading to soil erosion and health risks over time. Tarping offers a sustainable and cost-effective solution that addresses both issues.

Carly Strauser, graduate research assistant and co-author of the guide, explained, “Tarps can provide many of the same functions tillage does, such as killing weeds or decomposing cover crops. They are a great investment for growers and are relatively inexpensive because they are multifunctional and reusable.”

The publication outlines two main tarping techniques—occultation and solarization. Occultation involves using black and white tarps to block sunlight, effectively preventing weeds from photosynthesizing.

In contrast, solarization uses clear tarps to generate heat and kill weeds through high soil temperatures.

Ajay Nair, professor and chair of ISU’s Department of Horticulture, noted, “Spring temperatures in the north central United States are typically not warm enough to terminate weeds via solarization,” suggesting that occultation may be more effective in cooler climates.

Field studies showed that black and white tarps worked without the need for additional cultivation, while clear tarps and control plots needed further weed removal before planting cash crops.

This four-page guide is now available for free download from the ISU Extension Store, offering a practical tool for farmers seeking eco-friendly and efficient weed control in vegetable systems.

Photo Credit: iowa-state-university