Plant nutrients from organic residues in green house vegetable production – Solid fraction of bio fertilizers as substrate and nutrient source

Today, mainly peat is used as a substrate for cultivating potted plants and vegetables. The use of peat is questioned in many countries when it is considered that peat bogs are overexploited and that the mining causes interference with sensitive ecosystems and greenhouse gas emissions, and should therefore be reduced. In organic production, it is also necessary to have an organic substrate that accounts for a part of the plants nutrient demand. The project studies blends between the solid fraction and mainly peat, but also other substrates. Growth and quality are studied while nutritional assets are studied using extraction methods and the system's nutritional budget is calculated. Substrate physical properties such as porosity and water retention ability are very important for forming an appropriate substrate in potted cultivation and are therefore studied for the various mixtures.

Preliminary results show good results in terms of nutritional supply to the plants and the substrate's physical properties.