Abstract: The present invention relates to a low-density material element for use as protective packaging. The material element consists of a multi-layered body of a corrugated material which is lined on one of its sides. Thus the neighboring corrugated layers lie adjacent one another with a common lining layer without interlocking with one another and without being compressed. The multi-layer body has an extension length (L, E) which is in a direction perpendicular to both the corrugation extension direction and the layering direction. The multi-layer body is characterized in that it is held together with a singly positioned fixation. This singly positioned fixation functions to allow neighboring corrugated layers to lie loosely adjacent one another without being compressed. Furthermore, the singly positioned fixation allows the corrugated layers to be slidable relative to one another in a direction perpendicular to the corrugation extension (S) on being bent in a plane towards the body material.

Abstract: A plant growth body for germinating seeds for promoting the development of a root system for a cutting is constructed from a plurality of corrugated layers. Each corrugated layer has a plurality of parallel ridges and valleys that form channels extending between the adjacent ridges. When the corrugated layers are stacked one on the other, the plant growth body is formed so that the channels extend through the body. The material of the corrugated layers is penetrable by the roots so that the roots can penetrate successive ones of the corrugated layers and channels respectively. Further, the material of the corrugated layers preferably promotes capillary liquid flow through the plant growth body so that the roots are supplied with water.