Improving Citrus Yield and Fruit Quality with Nova CalPhos^®

Nova CalPhos® combines phosphorus, potassium, and calcium in a highly soluble, chloride-free formulation that supports root development, fruit set, and peel strength in citrus. By delivering these key nutrients efficiently through fertigation or foliar application, growers can improve yield consistency, enhance fruit quality, and reduce physiological disorders.

Balanced nutrition is one of the most important drivers of citrus performance. While nitrogen often receives the most attention, the value of other nutrients should not be forgotten. Phosphorus, potassium, and calcium play a decisive role in fruit set, sizing, and quality. When these nutrients are supplied in the right form and at the right time, they directly influence both yield and marketability.

Why Citrus Requires Balanced P, K, and Ca Nutrition

Citrus is a perennial crop with continuous nutrient demand and a strong dependence on nutrient balance to maintain productivity and fruit quality. Citrus orchards require particularly high inputs of potassium, alongside sufficient phosphorus and calcium to sustain fruit development and structural integrity.

Phosphorus acts as a key component in plant energy transfer, supporting root growth, flowering, and fruit set. It is also essential for fruit quality, specifically the formation of sugars and the structural integrity of juice vesicles. Potassium regulates water balance, sugar accumulation, and juice content, making potassium the most influential nutrient for fruit quality. Calcium strengthens cell walls, improves peel integrity, and reduces disorders such as rind breakdown and creasing.

However, delivering these nutrients efficiently is not always straightforward. Calcium mobility in plants is limited, phosphorus can become fixed in the soil, and potassium demand peaks during fruit development. This creates a strong case for targeted, highly available nutrient sources.

Maintaining citrus productivity requires ongoing balanced nutrition

What Makes Nova CalPhos® Different?

Nova CalPhos 0-57-17+7CaO is a unique, fully water-soluble fertilizer combining phosphorus, potassium, and calcium in a single formulation.

It is designed for fertigation and foliar application, offering:

• High solubility and rapid nutrient availability
• A chloride-free, low-sodium composition suitable for sensitive crops
• A low salt index, reducing the risk of phytotoxicity
• An acidic reaction that can improve nutrient uptake under alkaline conditions

This combination allows growers to supply three essential nutrients simultaneously, particularly during periods of high demand such as flowering and early fruit development.

Supporting Strong Flowering and Fruit Set

Phosphorus is critical during early growth stages, especially for flowering and fruit set. In citrus, insufficient phosphorus during early growth stages can limit root activity and reduce the tree’s ability to sustain a high fruit load. In addition, phosphorus deficiency during the fruit development stage will cause premature leaf-drop and smaller, coarser fruit with thick rinds and hollow centers.

Applying Nova CalPhos® during pre-flowering and early fruit set provides readily available phosphorus, supporting:

• Uniform flowering
• Improved fruit set
• Strong early fruit development

At the same time, calcium contributes to cell division and early tissue formation, helping establish fruit structure from the earliest stages.

CalPhos improves quality of Honey Pomelo fruit

Enhancing Fruit Size, Juice Content, and Sugar Accumulation

Potassium demand in citrus peaks during fruit enlargement and maturation. It regulates carbohydrate transport and water balance, directly influencing:

• Fruit size
• Juice content
• Sugar accumulation (Brix)

By delivering potassium in a highly available form, Nova CalPhos® supports efficient fruit filling and improves internal fruit quality.

The inclusion of calcium alongside potassium is particularly valuable, as it helps maintain cell wall strength during rapid fruit expansion, reducing the risk of structural weaknesses.

Improving Peel Strength and Reducing Physiological Disorders

Calcium plays a central role in citrus fruit quality. It strengthens cell walls and improves peel integrity, which is essential for both marketability and postharvest performance.

Consistent calcium supply helps reduce:

• Rind breakdown
• Creasing
• Fruit splitting

Because calcium is relatively immobile within the plant, it must be continuously available in the root zone or delivered via foliar application. Combining calcium with phosphorus and potassium in a soluble formulation improves delivery efficiency, particularly at critical growth stages.

Increasing Nutrient Efficiency Through Fertigation and Foliar Feeding

Modern citrus production increasingly relies on fertigation and foliar nutrition to improve nutrient-use efficiency.

Nova CalPhos® is particularly suited to these systems due to its:

• High solubility (up to 630 g/L at 20°C)
• Compatibility with other fertilizers
• Low risk of clogging irrigation systems

This allows precise nutrient application aligned with crop demand, reducing losses and improving uptake efficiency.

Foliar application can also be used to rapidly correct deficiencies or support the crop during high-demand periods, particularly when root uptake is limited by soil conditions.

Practical Positioning in Citrus Nutrition Programs

Nova CalPhos® fits best within a balanced nutrition strategy rather than as a standalone solution. It is especially effective:

• During pre-flowering and flowering (to support fruit set)
• During early fruit development (to support cell division and structure)
• In high-pH or calcareous soils where phosphorus availability is limited
• In intensive fertigation systems aiming to optimize nutrient delivery

By integrating Nova CalPhos® into a broader fertilization program, growers can better match nutrient supply with crop demand throughout the season.

A Smarter Way to Deliver Key Nutrients in Citrus

Citrus yield and quality are closely linked to how effectively nutrients are delivered, not just how much is applied. Combining phosphorus, potassium, and calcium in a single, highly available formulation simplifies nutrient management while improving agronomic outcomes.

Nova CalPhos® offers a practical tool for growers looking to enhance fruit set, improve fruit quality, and achieve more consistent yields in modern citrus production systems.