2025 Dutch Fertilizer Application Norms

This guide explains how the FDM Calculator determines the official Dutch legal usage norms (gebruiksnormen) for nitrogen and phosphate for the year 2025. These calculations are essential for ensuring your farm management plan complies with national environmental regulations.

The FDM Calculator automates these complex calculations based on your specific farm, field, and cultivation data. It calculates three key norms:

• Nitrogen Usage Norm (Stikstofgebruiksnorm): This norm sets the maximum total effective nitrogen (in kg N/ha) that can be applied to a field. The calculation takes into account the main crop, the geographical location (including NV-gebieden), and the soil region.
• Phosphate Usage Norm (Fosfaatgebruiksnorm): This norm defines the maximum amount of phosphate (in kg P₂O₅ per hectare) that can be applied to a parcel of land. The maximum is determined by the land use type (grassland or arable land) and the phosphate status of the soil.
• Animal Manure Usage Norm (Dierlijke Mest Gebruiksnorm): This norm defines the maximum nitrogen from animal manure (in kg N/ha) that can be applied. The calculation is based on the farm's derogation status and the field's location.

For more detailed information on these norms, please refer to the specific pages for each one.

Official Source & Disclaimer

The calculations in this document are based on the official 2025 norms published by the RVO (Rijksdienst voor Ondernemend Nederland). While we strive for accuracy, this document is for informational purposes only.

Always consult your agricultural advisor for definitive guidance and values tailored to your specific situation. FDM is not liable for any discrepancies or decisions made based on this information.

How the Calculator Works: Required Data

To calculate the norms for a specific field, the FDM Calculator requires the following information for the 2025 calendar year.

• Farm Details:

  • Derogation Status: Does the farm have a derogation permit for 2025? This is a critical factor for nitrogen and animal manure norms.

• Field & Location:

  • Field Location: The precise geographical coordinates of the field are used to determine if it falls within special regulatory zones, such as Nutrient-Polluted Areas (NV-gebieden), Groundwater Protection Areas (GWBG-gebieden), or specific soil regions (sand, clay, peat, loess).

• Cultivation Plan for 2025:

  • Main Crop (hoofdteelt): The primary crop grown on the field. The calculator identifies the main crop as the one with the longest cultivation period between May 15th and July 15th.
  • Crop Variety: For certain crops like potatoes and flowers, the specific variety can result in a higher or lower nitrogen norm.
  • Cultivation Dates: The start and end dates of cultivation are crucial for time-sensitive norms, such as those for temporary grassland.

• Latest Soil Analysis Data:

  • Phosphate Levels: The P-CaCl2 (or P-PAE) and P-Al values from your most recent soil test are used to classify the soil's phosphate status, which directly determines the phosphate usage norm.