Nutrient management plans

A nutrient management plan considers the optimal use of all available nutrients to ensure profitability of the crop and reduce environmental impacts.

Why produce a nutrient management plan?

There are two main reasons for producing a nutrient management plan: agronomic and compliance.

The organisation of information needed for a good plan will help show where improvements could be made. A comparison of intended and actual actions will add to experience for future years.

The information also will demonstrate compliance with nutrient regulations (e.g. nitrate vulnerable zones) or show where adjustments to farm practices are needed.

Key guiding principles

A nutrient management plan should be recorded in hard copy or electronic form so that it can be reviewed and updated easily. A forward-looking, dynamic plan is a practical tool to be used routinely in nutrient management.

It is not just a record of nutrient use to demonstrate compliance. It follows the philosophy of using the right amount, at the right time, in the right place, on a healthy soil.

The plan should cover all sources of nutrients:

• Soil
• Organic manures
• Manufactured fertilisers
• Biological nitrogen fixation

A nutrient management plan should be updated annually.

Objectives

The main objective is to match, as closely as possible, nutrient supplies to the requirements of the crops and herbage being grown. Achieving this will help meet other subsidiary objectives:

• Reducing the proportion of soils with high soil P indices (and so the extent of phosphorus movement from soil to water)
• Improving nitrogen use efficiency and reducing the movement of nitrogen from soil to water and air
• Maximising the economic benefits of nutrient use, for all nutrients
• Minimising the unwanted environmental impact of nutrient use, for all nutrients
• Ensuring compliance with nutrient regulations

What to record – farm details

• Twelve-month period to which plan applies: start date
• Farm name and holding number
• Risk map showing water courses, no-spread zones, boreholes, field manure heaps
• Dates of fertiliser spreader/sprayer calibrations and manure spreader checks

What to record – field details

Plans at start of season or before crop establishment:

• Field reference
• Date of soil sampling used for recommendations (pH, P, K, Mg) and indices or status recorded
• Previous crop
• Average annual rainfall
• SNS Index by field assessment method or measurement method
• If arable, date current crop established
• If grass, method of management (grazing, silage, hay)
• Market (e.g. feed/milling) and expected yield
• Major crop nutrient requirements, source (e.g. RB209) and amounts
• Expected organic manure applications and their nutrient supply
• Expected fertiliser applications and their nutrient supply
• Expected timing of applications of fertilisers and manures
• Check of expected compliance with relevant rules and regulations

 Records at end of season or after harvest:

• Date crop established and yield/quality achieved (if arable)
• Dates and amounts of nutrients applied in fertilisers
• Dates and amounts of nutrients applied in organic manures (total and crop available)
• Check of actual compliance with relevant rules and regulations
• If arable or silage only, offtake of P₂O₅ and K₂O in harvested crop and calculated balance

Remember the four-step plan for nutrient management:

1. Sample and test the soil in each field every three to five years to determine your soil nutrient supply.
2. Calculate the crop nutrient requirements.
3. Calculate the nutrient levels that will be supplied from organic manures.
4. Calculate the amount of fertiliser required, including product and rate.