Citrus growers are being advised to try kaolin clay to trick Asian citrus psyllids, the vector that transmits citrus greening.

Citrus greening is a bacterial disease that has decimated the Florida citrus industry since it was found in Florida citrus groves in 2005. Researchers are looking for a viable treatment or cure, with one area of focus being on controlling the Asian citrus psyllid, a tiny insect that transmits the citrus greening bacteria from citrus tree to citrus tree. Results of ongoing research have led UF/IFAS researchers to recommend Florida citrus growers try using kaolin clay to combat the psyllids, according to a Citrus Industry article. Read about it below.

Kaolin Clay Versus Asian Citrus Psyllids

According to the article, kaolin essentially “hides” the citrus trees from being detected by psyllids because it disrupts the wavelengths of light that psyllids use to identify trees as citrus. It’s a powder that has long been used on other fruit and vegetable crops. It’s mixed with water and sprayed on citrus trees. “As the water evaporates, a thin coating of kaolin remains behind on the leaves and other tree surfaces that were sprayed,” said Christopher Vincent, a citrus tree ecophysiologist and assistant professor with the Citrus Research and Education Center (CREC) in Lake Alfred. “It temporarily gives the leaf canopy a whitish color that’s very noticeable, and it provides several benefits to the treated groves.”

Other benefits of kaolin for citrus, according to the three-year studying being conducted by Vincent and CREC director and UF entomology and nematology professor Michael Rogers, include protecting citrus foliage from sun damage and increasing photosynthetic activity. Kaolin is a good option because it’s already in use in the ag industry and has little to no negative factors to contend with.

“We are encouraging growers to experiment with kaolin, because there’s a lot of potential upside to this material and not much risk,” said Rogers in the article. “Kaolin is inert, non-toxic and widely available. We think it’s worth a look, and UF/IFAS is conducting studies now to determine how we can optimize its usefulness for citrus production.”

The study is also looking at adjuvents to help the kaolin stay on the leaves longer and stretch the cost of the treatment for citrus growers. “We’re confident in saying that growers should consider using kaolin, but from there it’s a question of whether it makes financial sense for your operation,” said Vincent in the article. “Frankly, one of the biggest barriers that causes growers to hesitate is the expense — kaolin typically costs around $40 to $50 per acre, per application, and it needs to be reapplied after you’ve had 2 or 3 inches of rain.”

Griffin Fertilizer is committed to helping both growers and ranchers make sound agronomic and economic decisions in order to maximize the health of their grove and pasture. As a full-service custom dry & liquid fertilizer blender and crop protection product distributor, we will continue our mission to further advance Florida agriculture. For questions or concerns about your farm or pasture, contact us and one of our team will be in touch.