PURPOSE: To effectively use an inclined ground by injecting a vegetation material consisting of water absorptive polymer, seed and sand to cavities on a base plate surface, setting a base member provided on the rear side toward mountain side, and piling a retaining wall constructing members.

CONSTITUTION: A vegetation plate 6 is formed by providing a flat base member 10 on the rear side of a base plate 7 consisting of porous concrete, and injecting a vegetation material consisting of water absorptive polymer, seed and sand into the cavities of the surface 7a. When a retaining wall 5 is constructed in a graveyard constructing site 1, the plate 10 is faced to a grave building ground 3 side on high ground side, and a concrete placing channel 11 having a determined width W2 is formed between it and the cut face 3a of the ground 3. Concrete 4 is placed in the channel 11 and cured to construct the retaining wall 5, and the set state is kept without deformation after curing to grow a plant. Thus, the land having an inclination or difference in level can be effectively utilized.