University of FloridaSolutions for Your Life

Download PDF
Publication #HS1373

Movement of Plant Nutrients1

Tripti Vashisth and Chris Oswalt2

Soil-Applied Nutrition

  • Plants uptake nutrients when they are in a water solution.

  • Soil-applied nutrients are moved into the root during water uptake and therefore distributed in the tree along with water.

  • Mobile and immobile nutrients have an equal and uniform distribution in all parts of the plant.

  • Granular fertilizer, controlled-release fertilizer, and fertigation are all soil-applied fertilization methods.

Huanglongbing (HLB) Consideration

  • HLB-affected trees have a small root system; therefore, the nutrient uptake capacity of roots is limited.

  • The constant availability of nutrients is critical.

Figure 1. 

During the water uptake by the plant, the dissolved mineral nutrients get taken up by the plant and distributed throughout the canopy.


Credit:

Tonya R. Weeks, UF/IFAS CREC


[Click thumbnail to enlarge.]

Foliar-Applied Nutrition

  • Nutrient sprays should be timed at two-thirds-expanded to nearly fully expanded young leaves.

  • Mature leaves with thick leaf cuticles limit nutrient uptake.

  • Even when foliar sprays are applied at the right time, immobile nutrients can get locked in leaves and cannot move into growing leaves, roots, or fruit; as a result, their distribution within the plant is poor.

Figure 2. 

The availability of soil-applied nutrient is dependent on soil pH.


Credit:

Tonya R. Weeks, UF/IFAS CREC


[Click thumbnail to enlarge.]

Soil pH and Nutrient Interactions

  • At high soil pH, most of the micronutrients bind to the soil and become unavailable for plant uptake.

  • At extremely low soil pH, most of the macro- and secondary nutrients become unavailable for plant uptake.

  • The goal is to have the right soil pH range for nutrient uptake.

  • The preferred range for soil pH in Florida citrus production with HLB-affected trees is 5.8–6.5.

Movement of Mobile Nutrients

  • Mobile nutrients move to areas of active growth within the plant.

  • Nutrients move in all directions.

  • These nutrients are transported via xylem and phloem.

  • Deficiency symptoms appear first in older leaves, and if the deficiency is not corrected, they show up in new growth.

  • Mobile nutrients include Nitrogen (N), Phosphorus (P), Potassium (K), Magnesium (Mg), and Sulfur (S).

  • Soil- and foliar-applied nutrients are both adequate.

Figure 3. 

Mobile nutrients move in all directions throughout the plant.


Credit:

Tonya R. Weeks, UF/IFAS CREC


[Click thumbnail to enlarge.]

Movement of Immobile Nutrients

  • Immobile nutrients do not redistribute within the plant.

  • These nutrients are transported only via xylem.

  • Immobile nutrients do not move to areas of active growth.

  • Deficiency symptoms show up in the new growth first, and if not corrected, they will show up in older leaves.

  • Immobile nutrients include Calcium (Ca), Iron (Fe), Zinc (Zn), Copper (Cu), Manganese (Mn), Boron (B), and Molybdenum (Mo).

  • Foliar applications have limited efficacy and distribution in the plant.

Figure 4. 

Immobile nutrients do not move throughout the plant and are locked in the mature (old) growth.


Credit:

Tonya R. Weeks, UF/IFAS CREC


[Click thumbnail to enlarge.]

Footnotes

1.

This document is HS1373, one of a series of the Horticultural Sciences Department, UF/IFAS Extension. Original publication date November 2020. Visit the EDIS website at https://edis.ifas.ufl.edu for the currently supported version of this publication.

2.

Tripti Vashisth, assistant professor, Horticultural Sciences Department, UF/IFAS Citrus Research and Education Center; and Chris Oswalt, Extension agent IV, UF/IFAS Extension Polk County; UF/IFAS Extension, Gainesville, FL 32611.


The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other UF/IFAS Extension publications, contact your county's UF/IFAS Extension office.

U.S. Department of Agriculture, UF/IFAS Extension Service, University of Florida, IFAS, Florida A & M University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.