Essential Nutrients During Fruit Set and Sizing

June 2021

We are well into June and the heat is here to stay for a while. Citrus fruit is sizing and that means that essential nutrients are in high demand during this growth stage. Drought and heat stress are major concerns during this time, as they can damage shoot and root growth. Another issue that arises from drought and heat stress is salt damage. We all enjoy a little salt here and there on our favorite foods and snacks but excess salt in the soil is not a good thing. Sodium suppresses root growth, destroys soil structure, limits water availability to the plant, and competes for potassium uptake.

Healthy, nutrient balanced trees are more likely to pull through drought and other stresses than trees that suffer from nutrient imbalances or outright deficiencies.

fruit set and sizing

Citrus trees require optimum nutrition at each growth stage to promote better fruit size and tree health. During citrus fruit sizing, potassium (K) plays a crucial role. Citrus fruit removes large amounts of potassium compared to all other nutrients. Potassium is necessary for many plant functions such as the formation of sugars, protein synthesis, cell division and growth. Potassium supports trees by reducing many stresses such as drought and heat stress via turgor pressure and stomata operation. Potassium even works with phosphorus to stimulate and maintain root growth in citrus trees. Deficiencies in potassium lead to decreased yields and fruit size while optimum levels can increase yields, fruit size, fruit weight and acid content. Both potassium and calcium help to reduce the incidence of fruit splitting and creasing on fruit quality.

Calcium (Ca) is a key nutrient for overall citrus tree health. It can help crop roots thrive despite sodium damage. Soluble calcium improves soil structure by supporting aggregation and allowing for improved water infiltration and aeration. This increases the soil’s water holding capacity and improves the availability of soil moisture to plants.

Timing is critical for potassium and calcium applications. Available, soluble calcium is important for root health and results in increased water and nutrient absorption. Potassium is also important to reduce the incidence of fruit splits, especially during these hotter months when fruit will be growing quickly under uniform irrigations.

Benefits of YaraTera® NITRAKAL™

Provides a balanced formulation of nitrogen, potassium and calcium that are immediately available for uptake.

Nitrogen and potassium are important to achieving high marketable yields, uniformity of ripening, and proper brix in citrus fruit.

Calcium is vital for improving citrus tree and fruit quality, health, growth, and firmness, while also improving soil and root quality.

YaraTera Nitrakal applied during fruit-fill can assist in the exclusion of sodium in the rootzone, improve uptake of key nutrients like calcium and potassium, and optimize fruit yield and quality.



Learn more about the CompleteCitrus Solution for California Growers.

Vanessa Vicencio

Sales Agronomist at Yara North America - South Central Valley, California

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Vanessa Vicencio
Vanessa Vicencio
Sales Agronomist

South Central Valley, California