The greenhouse horticulture industry makes large-scale use of growing media, as these ensure better-quality produce in greater quantities. The current range of substrates, such as mineral wool and peat, have all the desirable properties – such as good water and air circulation – but are hardly sustainable. In response to this, Wageningen UR launched a project to develop a full-fledged alternative growing medium based on natural, high-fibre materials.

The biggest disadvantage to the current range of growing media is the energy-intensive production process (mineral wool) or the high CO2 emission (peat). Additionally, many substrates are not biologically degradable. Wageningen Research University is currently examining the possibilities offered by high-fibre materials such as grass, flax and hemp. It goes without saying that this growing medium will need to satisfy the demands imposed by the current users and quality criteria, but it should also be sustainable and biologically degradable. Only then will this contribute substantial added value the end consumer. A biologically degradable growing medium will, of course, not need to be disposed of separately after use.

Biggest challenge

According to the university, the biggest challenge – in the chain from raw material to ready-to-use product – is upgrading the natural high-fibre flow into a stable substrate capable of providing in a long-term and well-balanced moisture, oxygen and nutrient demand. A study will need to be launched to develop a process that will provide fibres with the right structure, strength, composition and affinity for water.

Partners for PPS project

Wageningen UR Food & Biobased Research already have a great deal of experience in modifying and enhancing the sustainability of fibrous materials. Their research makes use of various thermal, chemical, mechanical and biological technologies. The research department is currently seeking partners for its new Natural Growing Media project – as part of a partially funded public and/or private collaborative venture – with a view to developing a well-balanced, sustainable and biologically degradable natural substrate.

Source: Wageningen UR.