Nutrient Management Research Database

Citrus trees in commercial and dooryard plantings can exhibit a host of symptoms reflecting various disorders that can impact their health, vigor, and productivity to varying degrees. Identifying symptoms correctly is an important aspect of management, as inappropriate remedial applications or other actions can be costly and sometimes detrimental. Nutritional disorders addressed in this publication are an important aspect of citrus tree symptomology. Symptoms of deficiency or toxicity may have different forms of expression on foliage, stems, roots, and fruit, and may not in all cases resemble those illustrated in various publications. Symptoms can vary considerably from mild/incipient to chronic, particularly on foliage, and can also be expressed in leaf size. Because availability of some micronutrients like Zn, Mn, and Fe are soil-pH related, deficiency symptoms of these three elements may often occur simultaneously within a tree canopy and sometimes mask each other within a single leaf. To the untrained eye, nutritional disorders may be confused with herbicide, fungicide, physiological, and stress-related toxicities and physiological disorders. When in doubt, seek advice before committing to costly and perhaps inappropriate corrective measures.

This guide helps growers identify nutrient deficiency and toxicity problems they encounter in their fields.

microntrients, nutrien deficiency, nutrient toxicity, deficiency, toxicity, zinc, manganese, iron, nitrogen, phosphorus, potassium, calcium