As Hong Kong is a geographically hilly region, most of the territories developments are associated with slope stabilization and protection work. Shotcrete is the most commonly used methodologies to cover the soil slope and prevent surface erosion. Therefore, numerous natural vegetation woodland slopes are gradually reduced, environmental pollution is magnified, the ecological system is damaged whereas the macro climate is adversely affected. In 1998, Toyo introduced an advanced slope greening technique from Japan. By spraying the organic fibrous mulch materials on steep slopes and providing reliable planting medium, it is firstly named as Hydromulching in Hong Kong in the project of Smithfield Road, Hong Kong, Contract No. HY/94/20.

Three important elements of Hydromulching are turf reinforcement mat, fiber soil and erosion control mat. Turf reinforcement mat is a 3-dimensional PVC coated rhombic galvanized wire mesh. The function of the mat is to reinforce the cohesiveness of fiber soil over the slope. Fiber soil is the organic mulch material, which is the mixture proven to be gas permeable, strong in retaining water and have long lasting nutrient for the well establishment of grass. The bio-degradable erosion control mat is made by coconut fiber, which is an environmental friendly material with low heat absorption rate and high moisture retaining capacity.

The system does allow the vegetation itself to create an equilibrium environment and encourage primary and secondary germination of the vegetation on steep soil slopes with slope gradient up to 75o, or gentle non-soil slope with slope gradient up to 60o.