The present invention relates to the production of propagation plugs, primarily small blocks of sphagnum for the growing of cuttings and seed plants, and of the type consisting of a cylindrical block having an envelope of paper or a similar material and an associated filling of sphagnum or a corresponding substrate material. The paper is an air permeable composite sheet material comprising a) a biodegradable nonwoven sheet material； and b) a hot melt adhesive comprising at least 50% w/w of one or more biodegradable bioplastics. The hot melt adhesive is supplied to at least a part of a face of the biodegradable nonwoven sheet material.
