In the present invention a method for manufacturing a self-supporting structure used in germination of seeds and plants growth and a process for producing the same is presented. The self-supporting structure is obtained by mixing a growth medium with a binding agent, which is solely or mainly a fibrous material. In preferred embodiments, the fibrous embodiment is biodegradable. The invention discloses a process wherein the growth medium and the binding agent are mixed followed by shaping into the desired dimension of the self-supporting structure.