Results of Microbial Soil Amendments in HLB-Infected Grove

Approximately 40 people trekked into a Premier Citrus Management grove in Saint Lucie County on December 6 to learn that microbial soil amendments haven’t increased yields in an HLB-infected grove. Daniel Bott, Premier Citrus division manager for approximately 5,000 acres, including the trial site off Indrio Road, comments on the results.

“There seems to be some differentiation between the products,” Bott says. “However, it’s difficult to visibly tell any additional benefit” when the treated plots are compared to untreated control plots.

Bott says the results are disappointing “to a point. However, over the last few years we’ve learned some lessons about citrus production and have made headway in this property in particular and look forward to hopefully being able to continue to grow a crop on it.” He attributes the headway to “trying to do everything that we can to mitigate stress … Drainage and irrigation are probably the two most important and then making sure that trees don’t become nutrient deficient.”

“I don’t believe I’ll be expanding any additional usage (of microbial soil amendments) in the future,” Bott concludes. “At the end of the day, we are trying to do everything that we can to grow a healthy, productive citrus tree. But there has to be an increase in yields to make sure that the products remain commercially viable moving forward.”

Citrus Research and Development Foundation researcher Jim Syvertsen, a retired University of Florida researcher, served as project manager for the trials on the Premier Citrus Management property. The trials, established in 2014, were conducted on 6-year-old Valencia oranges on Swingle rootstock. Five commercially available microbial soil amendment products were compared.