Huanglongbing (HLB) or citrus greening is a bacterial disease vectored by the Asian citrus psyllid (ACP) and causing mottled leaves, tree decline, and yield loss.  Vector control and foliar nutrition are widely employed in Florida and elsewhere to respectively slow the spread of HLB and mitigate debilitating effects of the disease.  A replicated field study was conducted in a 5.4-ha commercial block of young ‘Valencia’ orange trees through four harvests employing a factorial design to evaluate individual and compound effects of a popular foliar nutrient program and threshold-based vector management.