The co-composted coal-compost substrates in the TOPKO project are being analysed for their suitability in terms of plant compatibility. In addition to chemical-physical substrate analyses, the main focus is on plant growth.

Various crops with different sensitivities to the substrate properties grow in the coal compost substrates until the end of the year. The crops are then assessed. This allows a statement to be made as to the extent to which the substrates are suitable for the crops or how the substrates need to be adapted to the plant requirements in the next step.

Image: Planting trial with laurel cherry (foreground), St John's shrub (background) and arborvitae (background) in the TOPKO project. S. Wessels