Citrus Nutritional Summary

It is essential to implement a balanced nutrition including macronutients and micronutrients in order to achieve the best results possible for your crop. Every nutrient plays a specific role on citrus production.

Macronutrients

Nitrogen and potassium are the most important nutrients for yield in citrus production. Calcium is also essencial, specially for fruit quality.

Nitrogen

Nitrogen is one of the most critical nutrients for increasing citrus tree growth and crop yields. As much as 1.78lb/ac of N per day is needed during fruit enlargement.Nitrogen and calcium are normally applied as 3-5 roughly equal split applications made during the growing season – particularly during periods of new growth. 
Fertigation of the macronutrients in general allows for better timing and greater efficiency of the nutrients. Nitrogen can be increased to meet its periods of peak demand.

Phosphate

Phosphorus is a component of nucleic acids and lipids and is important in metabolism, energy transfer, and photosynthate transport. 
While not needed in large quantities, the correct balance of phosphorus to other nutrients is critical. 
It is particularly important during early tree growth on new groves. In the long term, regular phosphorus applications will maintain the yield and fruit quality of mature trees.

Potassium

Potassium is one of the most critical nutrients for increasing citrus tree growth and crop yields. During maturation, K-demand increases in the fruit and rates of up to 1.78 lb/K/ac/day need to be supplied. Potassium nitrate is the preferred fertilizer during fruit growth, along with calcium nitrate. Potassium application rates can be increased to meet its periods of peak demand.Fertigation provides better timing and greater efficiency.

Calcium

Calcium nutrition is also important, particularly during the early stages of growth and throughout fruit enlargement. Calcium is the most widely found element in the citrus leaf and multiple applications during the season produce high yielding crops with the highest fruit quality.
Fruit removal figures show that more N and K are removed than any other nutrient.
Calcium is the third most utilized nutrient. It is important to take note of the level of nutrients removed in the fruit. Amounts vary significantly between citrus types.

Magnesium

Magnesium can be maintained at a constant rate throughout the season.

Sulfur

Sulfur is usually targeted to influence fruit set.

Micronutrients

While much lower levels of micronutrients are needed to satisfy yield and quality crop production, the correct balance of these trace elements is essential. Iron, zinc, manganese and boron are the micronutrients needed in the largest quantities to ensure that growth and quality is not limited.

Boron

Boron is one of the micronutrients needed in the largest quantities to ensure that growth and quality is not limited. It's usually targeted to influence fruit set, while other micronutrients are applied during periods or flushes of active growth.

Copper

Copper in citrus affects photosynthesis, plant protein production, pollen viability and therefore fruit set, respiration and water use efficiency. 
Copper can increase total juice content of the fruit. However, excessive use may delay fruit ripening.

Iron

Iron deficiency is commonplace and widely recognized. The most obvious effects are restricted fruit set and reduced fruit size. This results in a lower yield. Poor supply of iron can also delay fruit ripening and harvest. The degree of deficiency and response to Fe varies according to citrus type and rootstock. Iron also has a direct effect on crop quality improving the levels of total soluble solids in oranges and mandarins as well as increasing the TSS/Acidity ratio.

Manganese

Manganese is one of the micronutrients needed in the largest quantity to ensure that growth and quality is not limited. 
Dry applied may become complexed in the soil and are more slowly taken up. Foliar application or fertigation of micronutrients minimizes in-season deficiencies as they are quickly adsorbed by the plant.

Molybdenum

Molybdenum is best applied to the leaf.

Zinc

The main roles of zinc are as a cofactor of enzymes and involvement in the production of growth regulators responsible for internode elongation and chloroplast development.