Fertilization

In agriculture, sewage sludge and composted organic waste are used to return nutrients to the soil. These materials contain many important elements that plants need to grow—such as nitrogen, phosphorus, potassium, and organic matter. That is why they are also called secondary raw material fertilizers.

To prevent harmful substances from entering the soil, Germany has clear regulations set forth in the Sewage Sludge Ordinance and the Biowaste Ordinance.

Documentation Requirement

Operators of facilities that process sewage sludge or non-quality-assured organic waste must, with the competent authority:

• Submit advance notices of planned applications for review and
• Submit completion reports detailing the actual amount applied.

The reports, along with the declaration, must also be provided to the receiving farmer so that fertilization can be carried out in accordance with best professional practices.

This makes it possible to verify at any time that everything is proceeding correctly and safely.

Farm manure—which includes, for example, liquid manure, solid manure, or digestate from biogas plants—is used in agriculture as a natural fertilizer. The Agricultural Manure Transport Ordinance (WDüngV) regulates how these materials may be delivered, transported, and received—both within Germany and for imports.

All parties involved are required to:

• accurately document the quantities, ingredients, and type of fertilizer, and
• Submit registrations and reports so that all processes remain traceable.

This ensures that farm manure is applied in an environmentally sound manner in accordance with best professional practices and that water bodies and soils remain protected.

For more information, sample forms, and detailed explanations, please visit the Kassel Regional Council's website.

Soil samples are a key tool in modern agriculture. They reveal how many nutrients are present in the soil and help farmers determine the correct fertilizer requirements—which protects the environment, saves money, and ensures healthy crops. The results provide clear information about which nutrients—such as phosphate, potassium, and magnesium—are present in the soil, what the soil’s pH level is, and how the soil should be fertilized.

Farmers in the Fulda district can receive financial subsidies (e.g., de minimis aid) for soil, forage, or fertilizer analyses. Hobby gardeners also benefit from this, as they often use too much or too little fertilizer—an analysis helps identify and avoid mistakes.

Procedure

1. Sample collection:
   Farmers take individual soil samples from several locations in the field, which are then combined into a composite sample (from a depth of 0–10 cm for grassland, and from the tillage depth for cropland).
2. Sample Transport
   : For shipping, the testing laboratory usually provides sample boxes or bags and accompanying documentation. Soil samples can be sent directly to the laboratory or dropped off at the Citizen Service Center; we will forward them to the Hessian State Laboratory. Sampling can also be carried out through other service providers, such as the district farmers’ association.
3. Laboratory Analysis:
   As standard, the laboratory analyzes the pH value and the levels of phosphate, potassium, and magnesium. Additional parameters can be requested for an extra charge (e.g., humus content, trace elements).
4. Fertilizer Recommendations:
   Based on the results, farmers receive recommended fertilizer application rates for their crops, tailored to soil type and expected yields.

 What Is Being Studied

• pH level: indicates the soil's acidity and affects nutrient uptake and soil structure
• Phosphate (P₂O₅): important for root and cell development
• Potassium (K2O): supports water balance and frost resistance
• Magnesium (MgO): essential for leaf color and protein synthesis
• Optional: If necessary, the humus content (Corg) and/or trace elements such as boron or zinc are also tested.

Legal and Practical Considerations

• For fields of 1 hectare or larger that are fertilized, the Fertilizer Ordinance requires a soil test for phosphate every 6 years.
• From a technical standpoint, it is recommended to repeat soil testing every 3 years as part of the crop rotation to ensure that fertilizer planning remains up to date.
• If fields are subdivided or the crop rotation is changed, additional soil tests are recommended.

Farmers in the Fulda district can receive financial subsidies (e.g., de minimis aid) for soil, forage, or fertilizer analyses.

The grant can be applied for by March 31 of the following year by submitting the invoice along with the application for county subsidies (available in the download section on this page).