Irrigation and Nutrition - UF/IFAS Statewide Citrus Research and Extension - University of Florida, Institute of Food and Agricultural Sciences

HLB-affected trees have a small and weak root system, resulting in limited water and nutrient uptake; therefore, making nutrients continuously available maximizes the uptake.
Each grove is unique due to several factors such as soil type, soil pH, location, irrigation water quality, soil organic matter, method of fertilization, irrigation scheduling, tree nutrient status, tree age, variety, vigor and HLB-severity.
Irrigation and nutrition programs should be customized to address these unique situations.

Increasing the frequency of irrigation enables water availability throughout the day and the tree experiences less water deficit.
Reducing the duration and increasing frequency reduces excess water drainage, thus keeping adequate water level in the top 6 inches of the soil.
Enhanced irrigation is highly recommended during dry times of the year, especially during March through June when bloom, fruit set and early stages of fruit development occur.

Resources

Reclaimed Water Videos

The goal of a nutrition program is a continuous availability of all nutrients throughout the year.
The focus of the nutrition program should be on leaf nutrient concentrations and not on the rate of nutrient applied.
Leaf nutrient analysis is an effective tool for assessing tree nutritional needs. It is recommended to do the analysis as many times as bulk fertilizer is applied to address tree nutritional needs.
Soil testing should be done annually, but careful consideration should be given to leaf tissue results. While a soil test may show high nutrient concentration, the nutrient may not be readily available to the plant.
A nutrition program should be a combination of soil- and foliar-applied nutrients.
Do not rely solely on foliar application for any nutrient.
Fertilizer programs should have all nutrients in the right balance and ratios.
Fertilizer should be placed in the wetted zone.
Schedule irrigation at the time of soil-applied fertilizer applications to optimize uptake.
Split fertilizer applications are encouraged.
- Fertigation: apply a minimum of 12 to 30 splits a year.
- Dry soluble fertilizer: 4 split applications a year.
When using controlled-release fertilizer, apply 2 to 3 times a year.

Resources

Davie Kadyampakeni
Associate Professor
863-956-8843
dkadyampakeni@ufl.edu

Sandra Guzman
Assistant Professor
772-577-7342
sandra.guzmangut@ufl.edu

Tripti Vashisth
Associate Professor
863-956-8846
tvashisth@ufl.edu