Use of Gibberellic Acid to Improve Health and Productivity of HLB-Affected ‘Valencia’ Trees

Abstract

The goal of this publication is to provide the latest gibberellic acid (GA) use recommendation to Florida citrus growers. Recently, a multiyear field trial conducted on ‘Valencia’ has shown that GA applied monthly from September to January can improve yield of HLB-affected trees on average by 30% compared to untreated trees. Although GA treatment cannot eradicate the pathogen that causes HLB in affected citrus trees, the current GA application recommendation can provide growers an alternative remedy to alleviate HLB symptoms and ameliorate the production issues that are associated with the disease, including yield decline, reduced fruit size, increased preharvest fruit drop, and rapid tree health decline, until a cure for HLB or complete HLB-resistant cultivars can be developed. Written by Tripti Vashisth, and published by the UF/IFAS Horticultural Sciences Department, April 2023.