Biogas digestate

Farm manure

According to the definition in the Fertilizer Act, farm manure includes substances that are produced during animal husbandry in agriculture (e.g. solid manure, liquid manure and slurry) as well as plant substances that are produced or generated during plant production or agriculture.  

Farm manure is a valuable natural fertilizer. However, their nutrient content varies considerably. It is therefore important to know the exact macro- and micronutrient content in order to ensure that fertilizers are applied in line with requirements and the environment. The chemical-analytical examination of farm fertilizers is carried out according to the VDLUFA and DIN examination methods.

Biogas digestate

Biogas digestate is a by-product of biogas production. Similar to liquid manure, for example, digestate is spread on agricultural land to supply plants with nutrients. Digestate from the fermentation of plant materials from agricultural, forestry or horticultural operations (also mixed with animal excrement) is considered a farm fertilizer. If other materials (e.g. biowaste) are also fermented, these are organic fertilizers according to the Fertilizer Ordinance, which are also subject to the Biowaste Ordinance.

Legal requirements

Fertilizers are generally subject to the requirements of the German Fertilizer Ordinance (DüMV). Among other things, it specifies the essential material properties of fertilizers and defines source materials.

The Fertilizer Ordinance (DüMV and EC 2003/2003) regulates the use of substances in accordance with the Fertilizer Ordinance (DüV) on agricultural land. It serves to protect water from contamination by nitrate from agricultural sources (Nitrates Directive). The DüV defines the so-called good professional practice for the application of fertilizers according to type, quantity and time.