Gwen completed a Master's in Science at NC State studying how colored plastic mulches affect soil microbial communities and plant health in organic hemp production, under the direction of Dr. Jeanine Davis.
Organic hemp growers in the humid Southeast are challenged by heavy rainfall and aggressive weeds, with no approved organic herbicides to fall back on. Many turn to plastic mulches for weed and moisture control, but different mulch colors change how much heat and light reach the soil, with ripple effects on soil temperature, carbon cycling, and the microbial life underground.
Working across seven on-farm sites over two years, the research found that darker mulches (black, red, and green) ran noticeably warmer than white or silver, especially in summer, but that mulch color had surprisingly little effect on cannabinoid content or on the makeup of soil microbial communities themselves. What did shift soil microbial diversity was a more complex mix of season, sampling depth, and site conditions. It's the kind of research that helps growers make smarter choices about plasticulture, balancing short-term productivity against the long-term health of the ground they depend on.
Big thanks to our sponsors for this project:
Check out our Instagram for the latest happenings at Black Trumpet: