COMPOSTS FROM RESIDUES OF ANAEROBICALLY TREATED RENEWABLE RESOURCES AND THEIR SUITABILITY IN GROWING MEDIA

Seven solid residues from anaerobically digested renewable resources were composted for use as growing medium constituent.
In three cases several bulking materials were added to the fresh residues in order to investigate whether there is a positive effect on the composting process.
Subsequently, some of the composted materials were tested in a plant trial with Scaevola aemula. Additives of coarse structured materials such as flax residues or wood chips are not necessary to optimize the composting process.
Composted digestion residues are most suitable as a growing medium constituent if the digested raw materials consist only of plant resources.
The composts can be used at up to 40% by volume.
A co-digestion of plant plus animal resources results in residues with high levels of P and sometimes also high levels of Zn and Cu.
This might cause poor plant growth and leaf damage especially with plants that are very sensitive to P such as Scaevola aemula.

International Symposium on Growing Media 2007

H.-J. Schmitz, E. Meinken

anaerobic digestion, compost, growing media, horticultural substrates, renewable resources, P-excess, Scaevola aemula

https://doi.org/10.17660/ActaHortic.2009.819.43