To obtain a flame retardant mulching material capable of manifesting flame retardance regardless of the tree species or sites of a material by using an aqueous emulsion and phosphoric acid, etc., and further a wetting penetrant for the purpose of improving the spreadability over fiber surfaces together in a pulverized material of a bark, etc.

This flame retardant mulching material is obtained by using an aqueous emulsion as a vegetative paste and phosphoric acid and/or a phosphoric salt as a flame retardant and further a wetting penetrant for the purpose of improving the spreadability over fiber surfaces together in a pulverized material of a bark and/or a woody part. The wetting penetrant is preferably a sulfonic acid type surfactant in the flame retardant mulching material. Furthermore, the aqueous emulsion is preferably an acrylic resin emulsion in the flame retardant mulching material.