In the Netherlands, Delphy tests 'local' potting soils in the CloseCycle project. Delphy will conduct various studies at its Research Nursery in Hazerswoude-Dorp with residual flows from the region. For this purpose, a local network is being developed with tree growers from Greenport Boskoop, the municipality of Alphen aan den Rijn and companies from various sectors. One of the studies is testing various peat-poor and peat-free potting soils based on local residual flows.
In May 2024, twelve different substrate mixtures were made from a wide range of renewable raw materials ranging from wood fiber and different types of compost from the region to fermented corn, biochar, Miscanthus, dry manure fraction, etc. Thujas have been potted in the mixtures. Delphy will monitor the growth of the plants in the different substrates.
