Biodegradable Mulch: Your Next Production Tool?

Vegetable extension-research personnel from Ohio, Kentucky, Tennessee, and Iowa met on October 5, 2018 to discuss ongoing work and to plan follow-up activities … all toward helping improve short- and long-term farm success. Biodegradable mulch (BDM) was among the most talked-about topics. Dr. Annette Wszelaki of the Univ. of Tennessee led the BDM discussion and she provides comments for VegNet readers below. Also, note that Dr. Wszelaki will expand on these comments and summarize the large amount of research that her and other teams in various states have been doing with BDM, including on commercial farms, at the OPGMA-led Ohio Produce Network Meeting in Dublin, OH in January-2019. That presentation will be an excellent opportunity to gain a thorough update on BDM and its possible place in your toolbox.

Comments and Photos by Dr. Annette Wszelaki, Professor and Commercial Vegetable Extension Specialist, Univ. of Tennessee

Plastic mulches provide many advantages for vegetable production, such as weed and disease management, earliness of harvest, increased yield and quality, and moisture retention. However, plastic mulch use is not without disadvantages, including the cost, labor and environmental issues associated with plastic mulch disposal. Biodegradable mulches (BDMs) offer a potential alternative if they can provide similar advantages to plastic mulch without the disadvantages.

BDMs can look similar to traditional polyethylene mulch (i.e., stretchy and black or white-on-black) or in the form of paper (brown or black, sometimes with creping to give it stretch). They can be laid with a standard mulch layer. BDM’s are designed to cover the soil during the production season, and then begin to degrade as harvest nears. At the end of the season, BDM’s can be tilled directly into the soil. There they will degrade into carbon dioxide, water, and the bacteria and fungi that eat them. The degradation rate varies depending on environmental conditions, but by spring, most remnants will have disappeared.

At the University of Tennessee, we have been working with BDM’s on a variety of crops (tomatoes, pumpkins, and peppers) for 10 years. We have found comparable yields and quality to traditional plastic mulch with these crops, but not all biodegradable mulches and crop responses are equal!

Want to learn more about biodegradable mulches? Come to the session Could biodegradable mulches replace plastic in your production system? at the 2019 Ohio Produce Network in Dublin, January 16-17, 2019. In the meantime, please contact Annette Wszelaki (annettew@utk.edu or 865.974.8332) or visit www.biodegradablemulch.org for more information. Many thanks to Jenny Moore, Jeff Martin, the East TN Ag Research and Education Center Farm Crew, and many students along the way for their contributions to this project.

Figure 1. Creped paper biodegradable mulch just after field laying.

Figure 2. Stockpile of polyethylene plastic mulch on a Tennessee tomato farm.

Figure 3. Biodegradable plastic mulch in the newly planted pepper field.

Leave a Reply

Your email address will not be published.