Hydroseeding is the spray-on application of grass seed, fertilizer, wood fibre mulch (the green stuff) and tackifier (an organically-based type of glue) used to produce lush new grass quickly and economically. Once sprayed, the green mat aids in water and soil retention and acts like a green house, speeding up the germination process. As your lawn grows the mat will decompose and add nourishment to the soil.