Use of Organic Fertilizer in Denmark

From 4-6 of April, 2017, representatives of Farmers’ Parliament experts in the framework of the project “GreenAgri” together with colleagues from Estonia visited livestock farms in Denmark.

In the program:

  • Farm inspection: Isbjerg Mølle, Varde, 620 cattle and 460 hectares of land
  • Århus University, Foulum. Food and Agriculture Research Institute

Søren Petersen.

Denmark is an intensive livestock farming country, where 90% of all organic fertilizers are slurry, 8% deep bogs (harvested twice a year), 1% slurry, 1% ejected from the barn every day – solids with slurry. Most or 86% of the slurry is incorporated in the spring, 10% in summer on grassland and 4% in autumn. Liquid storage is mainly stored in lagoon type storage (80-90%) with a capacity of 10-12 months. In order to reduce ammonia emissions, lagoons must be covered, straw or natural crust is used as the cheaper coating. 46% of all slurry are directly applied to the soil, 35% are used through rubber hoses and 19% are additionally acidified with sulfuric acid 2-3 l/m3. Acidification is carried out in enclosed special places where the pH is reduced to 5.5, in the trench storage room or on the field (when applied to the soil).

Due to the high density of animals, legislation stipulates stricter rules for spreading terms and nutrient elements – Nitrogen (N) and Phosphorus (P) in farms with more than 1.7 cattle units per ha. Max dose for pig manure is 170 kg N / ha / year. Cattle dung 170-230 kg / ha / year. The use of nutrients from organic fertilizers has improved through the use of precise technologies (studies), legislative provisions and farmers’ education in the last 30 years.

In Denmark 22% of the agricultural land is occupied by grassland, from them 56% plant conversion culture, 25% are used for pastures in dairy cows. In Denmark, the farm in average has 170 cows, with an average milk yield over 9000 kg.

We got acquainted with the management of organic manure on two farms Isbjerg Mølle, Varde (620 cattle and 460 hectares of land), Jacob Gade, Skals (250 cattle). The Foulum Institute for Food and Agriculture at the University of Aarhus has gained insights on the close collaboration of scientists with farmers in research and policy making. The main research topics: climate and natural resources, environment and bioenergy, biological production and quality of biodiversity, crop production. The institute employs 90 scientists with degrees and 68 PhD students. The results of the trials are quickly transferred to production as well as educated young farmers.

Danish Agricultural and Farm Advisory Service – SEGES ( we got acquainted with the work of its crop production department. Consultants advise on daily breeding technologies, selection of varieties, plant protection, fertilizer application, field trials and legislative proposals. As an example, 35,500 fertilizer plans were developed in 2016, covering 2.1 million ha (80% of the total agricultural land, as well as 1 100 field trials with fertilizers, pesticides, etc.