NOVELTY - Vegetable seedling matrix comprises coconut shell powder base material, alcoholic fermentation biogas feed, carbonized rice husk, biogas sludge, perlite and vermiculite in volume ratio of (15-30):(15-30):(15-25):(1-2):(5-10):(15-25). Coconut shell powder base material is obtained by treating expanded wet materials obtained from domestic and imported tile with coconut water. Alcoholic fermentation biogas feed is obtained by collecting residue obtained after extraction of cassava with alcohol and then performing anaerobic fermentation of obtained residue at high temperature.    USE - Vegetable seedling matrix used in soilless cultivating technique for growing vegetable seedling in factory.    ADVANTAGE - The vegetable seedling matrix is cost-effective and rich in nutrition.    DETAILED DESCRIPTION - Vegetable seedling matrix comprises coconut shell powder base material, alcoholic fermentation biogas feed, carbonized rice husk, biogas sludge, perlite and vermiculite in volume ratio of (15-30):(15-30):(15-25):(1-2):(5-10):(15-25). Coconut shell powder base material is obtained by treating expanded wet materials obtained from domestic and imported tile with coconut water. Alcoholic fermentation biogas feed is obtained by collecting residue obtained after extraction of cassava with alcohol and then performing anaerobic fermentation of obtained residue at high temperature. Biogas sludge is obtained by collecting sediment from biogas tank, drying obtained sediment and then crushing dried product. Carbonized rice husk is residue obtained after burning ashes. An INDEPENDENT CLAIM is included for a method for preparing vegetable seedling matrix, which involves:    (A) drying alcoholic fermentation biogas feed in presence of decomposing agent at high temperature to obtain product with moisture content of 25-35wt.% and then crushing dried product to obtain particles of size below 3mm;    (B) treating expanded wet materials obtained from domestic and imported tiles with coconut water to obtain coconut shell powder base material with moisture content of 40-50wt.%, where expansion coefficient of wet material is 4-6;    (C) treating biogas sludge with water (20wt.%) and then crushing obtained product to 50 meshes powder;    (D) mixing alcoholic fermentation biogas feed, coconut shell powder base material, biogas sludge, carbonized rice husk, perlite and vermiculite uniformly to obtain substrate;    (E) measuring physical and chemical index of substrate to adjust water content, total porosity, bulk density, gas and water ratio, electrical conductivity value and pH value; and    (F) packaging obtained product into bag to obtain desired product, where capacity of bag is 0.01-0.1m3.