How to improve Nutrient Use Efficiency

With fertiliser costs remaining under pressure and increasing scrutiny on environmental performance, making better use of the nutrients already available to the crop is increasingly important.

Nutrient Use Efficiency describes how effectively crops capture and use nutrients supplied by the soil, organic sources and applied fertiliser.

Nitrogen is a major part of that picture, and Nitrogen Use Efficiency remains an important measure in its own right. But crop performance depends on nutrients working together. Improving efficiency therefore means looking at the whole system: soil condition, nutrient availability, crop demand, timing, placement and the ability of the crop to take nutrients up and use them effectively.

There is no single product or intervention that delivers better Nutrient Use Efficiency. The strongest results come from combining good soil management, accurate planning, appropriate nutrition and well-timed agronomy.

What is Nutrient Use Efficiency and why does it matter?

At its simplest, Nutrient Use Efficiency is about getting more value from the nutrients available to the crop.

That means considering not only what is applied, but also what is already present in the soil, when nutrients become available and how effectively the crop can access and use them.

Improving nutrient efficiency can help to:

• Increase the value obtained from fertiliser and organic nutrient sources
• Improve crop performance without relying simply on higher input rates
• Reduce avoidable nutrient losses
• Support stronger margins
• Improve environmental performance
• Build greater resilience into the cropping system

For nitrogen specifically, Nitrogen Use Efficiency, or NUE, describes how effectively available nitrogen is converted into crop output.

On many farms, NUE may sit around 50–60%, while significantly higher levels can be achieved where soil, crop and nutrient management are working effectively together.

The important point is that nitrogen efficiency should not be considered in isolation. Limitations elsewhere in the system can prevent the crop making full use of the nitrogen available to it.

1. Start with soil condition

Efficient nutrient use starts below ground.

If soil structure, drainage, rooting or pH are limiting crop development, applied nutrients are unlikely to perform as effectively as they could.

Key areas to consider include:

• Soil structure: Compaction and poor aggregation can restrict rooting, water movement and nutrient uptake.
• Drainage: Waterlogged or poorly drained soils can reduce root activity and increase the risk of nutrient loss.
• Organic matter: Organic matter supports nutrient cycling, soil biology, water retention and soil structure.
• pH: Soil pH has a major influence on nutrient availability. Correcting pH can often be one of the most effective ways of improving the efficiency of nutrients already present in the soil.

Improving soil condition through appropriate cultivations, organic inputs, cover crops, drainage and liming where required provides the foundation for better nutrient use.

2. Understand what the soil and crop can supply

Before deciding what to apply, it is important to understand what is already available.

Soil analysis provides a starting point for understanding nutrient status, while more targeted testing can help refine decisions where greater precision is required.

Depending on the crop and situation, this may include:

• Routine soil analysis
• Soil mineral nitrogen testing
• Organic matter assessment
• Tissue testing
• Grain analysis
• Crop biomass or canopy assessment
• Historic yield and field performance data

The objective is not to collect data for its own sake. It is to build a clearer picture of nutrient supply and crop demand so that applications can be better matched to what the crop actually needs.

3. Apply nutrients with greater precision

Matching nutrient supply to crop demand is central to improving efficiency.

For nitrogen, this may include using soil nitrogen measurements, Green Area Index assessments, yield potential and grain protein data to refine applications.

The same principle applies more widely across crop nutrition.

The right rate, timing, source and placement will vary according to nutrient, soil type, crop growth stage and seasonal conditions.

Digital tools and decision-support systems can help bring these factors together, particularly where there is significant variation within fields.

The aim is not necessarily to apply less. It is to apply nutrients where, when and in the form they are most likely to deliver a return.

4. Think beyond nitrogen alone

Nitrogen often receives the greatest attention because of its cost and its influence on yield, but crop response depends on a balanced supply of nutrients.

Where another nutrient is limiting, increasing nitrogen alone may deliver little additional benefit.

Sulphur is a good example. It plays an important role in nitrogen metabolism and protein formation, and insufficient sulphur can reduce the crop's ability to use applied nitrogen efficiently.

Potassium is also important for water regulation, enzyme activity and crop resilience, while phosphorus supports rooting and energy transfer within the plant.

Micronutrients may be required in much smaller quantities, but deficiencies can still restrict crop performance.

Efficient nutrient management therefore means identifying the limiting factor rather than assuming nitrogen is always the answer.

5. Choose and manage fertiliser inputs carefully

The behaviour of nutrients after application can vary considerably.

For nitrogen in particular, losses through volatilisation, leaching and denitrification can reduce the proportion ultimately available to the crop.

Depending on the situation, options may include:

• Selecting the most appropriate fertiliser source
• Adapting timing to crop demand and weather conditions
• Using urease inhibitors where appropriate
• Considering stabilised nitrogen products
• Balancing nitrogen with sulphur and other required nutrients
• Improving application accuracy

The choice of fertiliser should form part of the wider nutrient strategy rather than being considered independently of soil condition, crop demand and seasonal risk.

6. Build rotation and crop resilience

Rotation influences nutrient demand, nutrient cycling, rooting depth and soil condition.

Different crops explore different parts of the soil profile and return different amounts and types of crop residue. Legumes and cover crops can also influence nitrogen availability and nutrient cycling within the rotation.

Where appropriate, growers may consider:

• Crop sequence and rooting characteristics
• Use of legumes within the rotation
• Cover crops
• Organic material availability
• Seed rates and establishment
• Approaches that improve rooting and early crop development

The objective is to create a system in which crops are better able to access and use the nutrients available to them.

7. Use biosolutions where they have a clear role

Biosolutions can form part of a wider nutrient management programme, particularly where they support crop development or nutrient acquisition.

Depending on the product and situation, their role may include:

• Supporting root development
• Improving nutrient uptake
• Helping the crop use available nutrients more effectively
• Supporting crop performance under stress
• Improving establishment and canopy development

They should not be viewed as a substitute for correcting fundamental soil or nutritional problems.

Their value is greatest where they address a clearly identified agronomic need and are used as part of an integrated programme.

8. Protect the crop's ability to use nutrients

Good nutrition only delivers value if the crop remains capable of using it.

Disease, poor rooting, lodging and environmental stress can all reduce nutrient capture or limit the crop's ability to convert nutrients into yield.

Crop protection and plant growth regulation can therefore influence nutrient efficiency indirectly by protecting green leaf area, rooting, crop structure and yield potential.

The objective is to maintain a healthy, functioning crop capable of making effective use of the nutrients already invested in it.

Bringing Nutrient Use Efficiency together on farm

Improving Nutrient Use Efficiency is not about chasing one number.

It is about understanding where nutrients come from, where they are being lost or under-used, and what is limiting the crop's ability to respond.

In practice, the greatest gains often come from bringing several areas together:

• Improving soil condition
• Understanding nutrient supply
• Matching applications more closely to crop demand
• Correcting nutrient imbalances
• Reducing avoidable losses
• Supporting strong rooting and crop health
• Measuring the response and adapting future decisions

The right approach will vary between farms, fields, crops and seasons.

That is why Nutrient Use Efficiency is best treated as an ongoing management process rather than a single intervention.

Speak to your agronomist

Every farm is different. Soil type, rotation, nutrient status, crop potential and seasonal conditions will all influence the most appropriate approach.

Speak to your Agrii agronomist to review nutrient efficiency on your farm and identify where improvements could deliver the greatest agronomic and financial value.