How to prevent hemp mites from entering your greenhouse

For growers contemplating — and who have begun — growing hemp as part of farm trials associated with UF's Institute of Food and Agricultural Sciences (IFAS) Industrial Hemp Pilot Project, this latest release focuses on lessons learned and provides detailed information on three major groups of mites. The mites, which can be lethal to hemp grown in Florida fields and greenhouses, are hemp russet mites, broad mites, and spider mites.

"These pests can attack hemp by distorting growth, causing defoliation and even killing plants," says Lance Osborne, a Professor of Entomology at the UF/IFAS Mid-Florida Research and Education Center. "A new video explores the most important groups of mites, how to identify them, the latest research available on chemical and biological control methods, and more."

Multiple resources and a 30-minute presentation are accessible at the Mites of Industrial Hemp in Florida website. Osborne narrates the video, while Juanita Popenoe, a UF/IFAS Extension agent specializing in commercial fruit production for Lake, Orange, and Marion counties, and Research Entomologist Cindy McKenzie of USDA's Agricultural Research Service co-authored the new document.

"Hemp is a relatively new crop for Florida, even though it has been around for hundreds of years," Osborne says. "There is limited availability of state-approved pesticides for use in hemp, and data is hard to find on efficacy or plant safety, but there are resources from multiple entities available and research continues to be conducted."

Among the critical insights for growers are recommendations on how to prevent mites from entering greenhouses and how to search for them in fields - a first and necessary step for growers. There is also an extensive look at the feeding damage and symptoms to look for on crops for each of the mites along with links to a fact sheet on the mites.

"Scouting is the foundation of any pest management program and is absolutely critical," Osborne says. "Most growers try to have someone scout crops for mites at least once a week. The UF/IFAS Mid-Florida Research and Education Center in Apopka holds an annual training program to teach new scouts the process."

Photo: Predatory mite Phytoseiulus persimilis feeding on a two spotted spider mite.

Source and Photo Courtesy of Greenhouse Grower

Source: Greenhouse Grower