Quantification of the amount of peat and substrate used in tree nurseries in Germany

The objective of the German peat reduction strategy is to reduce peat use in horticulture as a whole and in the different horticultural sectors. For the implementation and monitoring of the progress toward the objectives of the strategy, precise information on the substrate and peat quantities currently used in the individual branches of horticultural production are essential. There are no valid data on this yet. To fill this gap, an online survey with tree nurseries is conducted. The survey will remain open until end of December 2020. Preliminary results from 48 tree nurseries indicate that an average of 182.3 m³ is purchased per ha container area and year. Extrapolated to whole of Germany, this means that around 282,500 m³ of substrate is used per year for container production in tree nurseries. These substrates include 210,200 m³ of peat. The results also show that some tree nurseries already have experience with the use of peat alternatives in significant proportions and that currently the most relevant alternative is wood fiber. A previous study for Switzerland, estimated that 1 m³ peat causes the emission of 250 kg CO₂-equivalent. Applying this factor to the amount of peat used in tree nurseries in Germany would result in emissions of more than 52 kt CO₂-equivalent.