To obtain a bed soil for plant excellent in air permeability and water permeability, suitable for the germination of seeds, by using burned ash of an industrial waste.

An industrial waste is burned into ash and the burnt residue is roughly ground and the roughly ground residue is washed with water. Consequently, an alkali component and the finely granular residue is sieved with water to give the objective bed soil for plant using the burnt ash of an industrial waste.