Cascade utilization pathways for miscanthus as growing substrate in horticultural production

Miscanthus is a promising renewable feedstock for soilless substrates in terms of supply capacity, local availability, and beneficial ecosystem services. The multiple industrial applications of miscanthus provides both challenges and benefits as 1) feedstock competition from other industries and 2) potential new markets for used substrates with crop cultivation functioning as a cost-effective and 'green' pretreatment to tailor feedstock properties for other industrial applications. So far, there is a lack of an overview on how miscanthus as soilless substrates could be integrated into other value chains of the feedstock. Therefore, this paper aims to propose cascade utilization pathways for miscanthus substrates based on the literature and our own research. Potential miscanthus feedstock for soilless substrates include dry miscanthus biomass, composted bedding material, and biochar. After being used as soilless substrates, miscanthus could be reused for greenhouse crops or served as feedstock for further applications including combustion, biochar, biofuel, lignin biorefinery, and particleboard. This work highlights the possibility of using miscanthus substrates in a cascade manner, which will not only increase resource efficiency and by that sustainability, but also provide additional market to reduce feedstock competition.