Potting soils are mostly composed of inert raw materials (peat,perlite, coconut, mineral fertilisers…), that are characterized by a poor soil life, both with regard to the number and the diversity of the micro-organisms. However, micro-organisms are very useful: they will convert organic matter into nutrients for each other and for the plants. Moreover, the mutual competition between the different organisms slows down harmful organisms. As a consequence, diseases will have less chance of developing.
For this reason it is important to pay sufficient attention to the microbial activity and diversity in the substrate. In a healthy and fertile substrate with a diverse and active soil life, plants benefit from a better balance and an improved nutrient release. The risk of pathogen exposure will also decline. Plants develop a healthier root system and grow more vigorously, resulting in a lower rate of plant loss.