PROBLEM TO BE SOLVED: To discriminate the kind of agricultural material optimized corresponding to the growth condition of agricultural products and a method or using that material and to propose them to agricultural product producers. SOLUTION: Information on the agricultural products to be cultivated and areas and information on the present condition of the agricultural products are collated with the contents of an agricultural product cultivation information file containing information on weather, information on agricultural products, information on the soil of agricultural land, information on the growth condition of agricultural products and information on agricultural materials and the kinds of the agricultural materials optimized corresponding to the growth condition of the corresponding agricultural products in this file, and the methods for using the materials are discriminated.
