A shape-permanent or deformation-resistant growing medium in the shape of a block, that may hold one or more plants, consists of an active or inactive growing medium and an adhesive or binder providing shape and strength, said adhesive or binder being gypsum (calcium sulphate, CaSO.sub.4.2H.sub.20). By using gypsum as an adhesive or binder it is possible to make known growing media completely shape-permanent or deformation-resistant in a quite simple way enabling plants to grow and thrive absolutely normally, while the growing medium keeps its original shape under practically any circumstances. When the medium is no longer of use, it may be discarded without any problem and without any costs of disposal.