Patent ID: 7712252

Claim:
A method of manufacturing a culture medium on which plants can be grown, the method comprising the steps of: a) mixing I: a particulate base material, chosen from at least one of organic and inorganic materials, with II: a thermoplastic biologically degradable binding agent; b) positioning a first layer comprising a mixture of said base material and said binding agent, upon which a second layer of base material that is substantially free of binding agent is positioned, and optionally a third layer comprising a mixture of said base material and said binding agent; c) carrying out a shaping treatment to fold the first layer over the second layer or to move the first and third layer at both sides of the second layer toward each other, such that the second layer containing only base material is completely surrounded by either the folded first layer or the first and third layers, the surrounding layer containing said mixture of base material and binding agent; d) heating at least the binding agent in said surrounding layer using a heating agent selected from the group consisting of steam, infrared radiation, and magnetron radiation in order to at least partly fluidise the binding agent with the base material; e) cooling the mixture so as to substantially solidify the binding agent in said surrounding layer to bond together the base material in said surrounding layer.