Micronutrient fertilisers are playing an increasingly important role in modern agriculture.

As growers expect higher productivity, better crop quality and more efficient use of nutrients, fertiliser manufacturers are developing products that perform reliably across different growing conditions while delivering greater value.

Although micronutrients are required in relatively small amounts, incorporating them into a fertiliser is not always straightforward. The nutrient source, formulation technology, compatibility with other ingredients and manufacturing processes can all influence product quality and performance.

For manufacturers, understanding these considerations is becoming a valuable part of developing more advanced fertiliser products.;

This guide explores the role of micronutrient fertilisers, the trends shaping their adoption and the formulation technologies used in modern fertiliser development. It provides a practical resource for manufacturers looking to better understand this evolving area of plant nutrition.

Micronutrients have always been essential for plant growth. What has changed is the role they play in fertiliser development.

Traditionally, micronutrient fertilisers were used primarily to supply crops with the micronutrients they require and to address nutrient deficiencies where they occurred. Today, micronutrients are increasingly incorporated into complete fertiliser formulations, where they can complement other nutrients and contribute to the overall performance of the product. For manufacturers, this broader role means that micronutrient selection has become a strategic product development decision, alongside considerations such as compatibility, stability, nutrient availability and cost efficiency.

Plants require a balanced supply of nutrients throughout their life cycle. While nitrogen (N), phosphorus (P) and potassium (K) are required in the largest quantities, plants also need the secondary nutrients calcium (Ca), magnesium (Mg) and sulphur (S), and require several micronutrients.

Micronutrients are also commonly referred to as trace elements (TE), and in some markets as oligo-elements (OE) or MN. Although they are required in much smaller quantities than primary nutrients, each performs a specific function that cannot be replaced by another nutrient. Even small deficiencies can affect plant development, crop quality and yield.

The micronutrients most included in fertiliser formulations are:

• Iron (Fe)
• Zinc (Zn)
• Manganese (Mn)
• Copper (Cu)
• Boron (B)
• Molybdenum (Mo)

Together, these nutrients support a wide range of plant processes, including photosynthesis, enzyme activity, protein formation and nitrogen metabolism.

| Key takeaway: Micronutrients are required in small quantities, but they are essential for healthy plant growth and crop productivity.

Micronutrient fertilisers are designed to supply one or more of these nutrients in a form suitable for agricultural use. They are available in a range of product types, including granular, liquid, suspension and water-soluble fertilisers.

The choice of product type depends on the intended application and the objectives of the final fertiliser.

Growers expect more from every fertiliser application.

Beyond supplying nutrients, fertilisers are increasingly expected to deliver consistent crop performance across different soils, climates and production systems. Manufacturers are therefore developing products that provide greater value while meeting these expectations.

Micronutrients have become a significant part of this approach, supporting balanced plant nutrition within increasingly advanced fertiliser formulations.

Improving nutrient use efficiency (NUE) has become a priority across the agricultural industry.

While nutrient use efficiency is often associated with nitrogen and phosphorus, efficient plant nutrition also depends on an adequate supply of micronutrients. Many of the physiological processes involved in nutrient uptake, nitrogen metabolism, photosynthesis and growth require micronutrients to function effectively.

For manufacturers, this has increased interest in incorporating micronutrients into complete fertiliser formulations rather than treating them as standalone products.

| Industry Insight: Improving nutrient use efficiency is not only about supplying nutrients. It also involves ensuring plants can use nutrients efficiently throughout the growing season.

When crop prices are low or growing conditions are difficult, growers may become more selective about where they invest in crop inputs. For manufacturers, this makes it even more important to develop micronutrient products with a clear and measurable value proposition.

The value of a micronutrient fertiliser depends not only on the amount of nutrient applied, but also on how effectively that nutrient is made available to the plant. Complexing technologies can play a key role here. Lignosulfonate-complexed micronutrients help maintain nutrients in a plant-available form, which may support nutrient uptake following application.

This can be relevant both for preventing and correcting micronutrient deficiencies, depending on the crop, nutrient and application. Under challenging growing conditions, maintaining nutrient availability can be particularly important for crop performance.

When micronutrient products support nutrient uptake and crop performance, their economic contribution should be evaluated alongside the application cost. This means that a well-designed micronutrient fertiliser can be more than an additional input cost. It can be an investment in crop performance.

| Industry Insight: When input costs are under pressure, the question is not simply how much a micronutrient application costs, but what value the application can deliver.

The speciality fertiliser market has expanded rapidly over recent years. Rather than competing solely on nutrient content, manufacturers are increasingly developing products tailored to specific crops, production systems and market needs. Micronutrients have become a significant part of this trend, particularly in water-soluble fertilisers, liquid fertilisers, foliar products and premium NPK formulations.

As fertiliser markets become more competitive, manufacturers are looking beyond nutrient content to differentiate their products. Product consistency, ingredient compatibility and overall formulation performance have become increasingly important factors in product development.

As a result, the technologies used to incorporate micronutrients have become an important consideration in product development. Interest has grown in technologies that combine formulation flexibility, micronutrient performance and renewable raw materials.

| Key takeaway: The growing use of micronutrients reflects broader changes in fertiliser development. As manufacturers respond to increasing demands for performance, efficiency and product differentiation, formulation decisions have become more important than ever.

Incorporating micronutrients into a fertiliser is not simply a matter of adding another nutrient. Each formulation must balance agronomic performance, manufacturing requirements and product quality while remaining stable throughout production, storage and application.

This complexity explains why two fertilisers containing the same micronutrient content may perform very differently, depending on the form or source of the micronutrient.

The following sections outline some of the key considerations manufacturers evaluate during formulation development.

Micronutrients are available from a range of sources, each with different characteristics.

The choice of nutrient source can influence compatibility with other ingredients, nutrient availability, manufacturing efficiency and the overall performance of the finished product. Selecting the most appropriate source therefore depends on the objectives of the formulation rather than on the micronutrient alone.

Maintaining compatibility

Micronutrients must perform alongside other nutrients and formulation components.

Interactions between ingredients can influence product consistency, manufacturing processes and the quality of the finished fertiliser, making compatibility an important consideration during formulation development.

Achieving product stability

Fertilisers must maintain their quality throughout storage, transport and handling.

A stable formulation helps ensure that products remain consistent before reaching the grower, supporting both manufacturing quality and field performance.

Supporting nutrient availability

The effectiveness of a micronutrient fertiliser depends on more than simply supplying the nutrient.

The formulation influences how nutrients remain available after application, making formulation technology an important consideration alongside the nutrient source itself.

Balancing technical and manufacturing requirements

Successful formulations must satisfy both technical and practical requirements.

Manufacturers evaluate technologies not only for their agronomic performance but also for production efficiency, formulation flexibility, raw material handling and cost efficiency.

| Key takeaway: Developing a successful micronutrient fertiliser requires balancing multiple formulation objectives. The most appropriate solution depends on the product being developed and the challenges it is designed to address.

Selecting a micronutrient is only one part of developing an effective fertiliser. The technology used to incorporate that nutrient into a formulation can also influence product quality, manufacturing efficiency and field performance.

Different formulation technologies have been developed to meet different formulation objectives. Some prioritise cost-effective nutrient supply, while others focus on compatibility, stability or nutrient availability. The most appropriate choice depends on the fertiliser being developed, its intended application and the performance objectives of the final product.

The following sections introduce the main formulation technologies used in modern micronutrient fertilisers.

Inorganic salts

Inorganic salts remain among the most widely used micronutrient sources in fertiliser production.

Examples include zinc sulphate, manganese sulphate and copper sulphate. They are widely available, cost-effective and compatible with many conventional manufacturing processes, making them suitable for a broad range of fertiliser products.

Chelated micronutrients

Chelated micronutrients are designed to help maintain nutrient availability under a wider range of soil conditions.

By binding the micronutrient to a chelating molecule, they reduce interactions that can limit nutrient availability after application. This makes them particularly valuable where maintaining nutrient availability is a priority.

Their use depends on the intended application, formulation objectives and commercial considerations.

Complexing technologies

Complexing technologies provide another approach to incorporating micronutrients into fertiliser formulations.

A variety of complexing agents are available, including lignosulfonates, gluconates and amino acid-based technologies. Although they differ in chemistry, they are all designed to support formulation performance.

When comparing complexing technologies, manufacturers typically evaluate characteristics such as:

• Compatibility with other formulation ingredients
• Product stability
• Micronutrient loading capacity
• Manufacturing flexibility
• Nutrient availability

Each technology offers different advantages depending on the objectives of the final product.

| Key takeaway: No formulation technology is suitable for every application. The most appropriate choice depends on the balance between technical performance, manufacturing requirements and product objectives.

Sustainability is becoming an increasingly important consideration in fertiliser development. Alongside product performance, manufacturers are looking for technologies that incorporate renewable raw materials and support broader sustainability goals.

Manufacturers are increasingly evaluating renewable raw materials alongside technical performance, cost efficiency and product quality when selecting formulation technologies. Within micronutrient fertilisers, bio-based complexing technologies offer an alternative approach that can support compatibility, stability and formulation flexibility while using renewable feedstocks.

As with all formulation technologies, suitability depends on the requirements of the final product rather than on a single performance criterion. This growing interest has encouraged continued innovation in renewable formulation technologies, including lignin-based complexing technologies that support micronutrient fertiliser development.

Lignosulfonates are bio-based polymers derived from wood and have been used for decades across a wide range of industrial and agricultural applications.

In micronutrient fertilisers, lignosulfonates can act as complexing agents for metal micronutrients, helping support their solubility and stability within the formulation.

Lignosulfonates differ from other complexing technologies in their chemical structure and distribution of functional groups, which contribute to their solubility, compatibility and complexing behaviour. This chemical architecture contributes to solubility and compatibility while helping maintain micronutrients in complexed form and in solution across a wide range of formulation conditions.

For fertiliser manufacturers, this can translate into several advantages:

• Micronutrient complexing capacity
• Improved stability and solubility
• Compatibility with different fertiliser formulations
• Flexibility for micronutrient loading
• A bio-based alternative derived from renewable raw materials

For manufacturers, this combination can make lignosulfonates an attractive option when seeking a balance between formulation performance, flexibility and cost efficiency.

Not all complexing technologies behave in the same way. Lignosulfonates, gluconates and amino acid-based complexes differ in their chemistry, which can influence their stability and performance under different conditions.

For more than a century, we have developed solutions based on lignin chemistry. This experience enables us to support manufacturers with both formulation expertise and a reliable supply of bio-based raw materials. Today, we help fertiliser manufacturers develop micronutrient formulations for a wide range of crops, markets and production systems. Produced from renewable wood through our integrated biorefinery process, our lignosulfonates provide a bio-based alternative for micronutrient formulations while supporting compatibility, stability and manufacturing flexibility. Rather than offering a single solution for every application, we work closely with customers to understand their formulation objectives and identify the most appropriate technology for their products and manufacturing processes.

By combining renewable raw materials with decades of formulation expertise, Borregaard helps manufacturers develop differentiated fertiliser products that meet both technical and commercial objectives.

As micronutrient fertilisers continue to evolve, formulation technology will remain an important factor in developing products that combine agronomic performance, manufacturing efficiency and sustainability.

Understanding the strengths of different formulation approaches is an important first step. Manufacturers that successfully combine nutrient performance, formulation flexibility and sustainability will be best positioned to meet evolving market expectations.

With decades of expertise in lignin chemistry and renewable formulation technologies, Borregaard works alongside fertiliser manufacturers to help develop products that meet these evolving demands.