Biochar for Circular Horticulture: Feedstock Related Effects in Soilless Cultivation

Biochar has previously been used in growing media blends as fertilizer or for improving plant growth, disease suppression, and a sustainable replacement of peat. To achieve optimal circular horticulture, we propose here to reuse the biochar from spent media. However, it is unclear what extent feedstock determines mode action if use may encounter nutrient salt problems. Differences chemical characteristics, release, interaction leaching experiment effects on uptake, suppression strawberry greenhouse trial were studied 11 biochars either processed lignocellulosic biomass. A well-studied produced oak wood was set reference. Biochars characterized by higher electrical conductivity, extractable total concentrations compared with Especially first phase experiment, all showed most prominent reference biochar. The latter an important source phosphorus particular potassium. Only biochar, plants increased uptake phosphorus, potassium calcium, chlorophyll concentration. No Bortrytis cinerea no increase growth observed tested biochars. It concluded that can be recycled without adverse