PROBLEM TO BE SOLVED: To provide a technique which, in an artificial soil culture medium formed by putting together artificial soil grains, can continuously supply a cultivation-targeted plant with water for a long period and can highly control supply amount of water corresponding to the cultivation-targeted plant.SOLUTION: An artificial culture medium 100 includes a plurality of artificial soil grains 50 having a base part 10 which can absorb/discharge water. The artificial soil grains 50 consists of a plurality of kinds of artificial soil grains 50 respectively having different water absorption/discharge characteristics which indicate a state that absorbs water in the base part 10 or a state that discharges from the base part 10. The artificial soil grains 50 includes (a) a first artificial soil grain 50a which includes a porous body 10a formed by granulating a plurality of fillers 3 having a pore 4 as the base part 10, and (b) a second artificial soil grain 50b which includes a fiber lumpy body 10b formed by putting together fibers 1 as the base part 10.【課題】人工土壌粒子を集合してなる人工土壌培地において、栽培対象の植物に長期に亘って持続的に水分を供給したり、栽培対象の植物に応じて水分供給量を高度にコントロールすることが可能となる技術を提供する。【解決手段】水分を吸収／放出可能な基部１０を備えた複数の人工土壌粒子５０を含む人工土壌培地１００であって、複数の人工土壌粒子５０は、基部１０が水分を吸収する状態又は基部１０から水分を放出する状態を示す水分吸放出特性が夫々異なるように設定された複数種の人工土壌粒子５０で構成され、複数種の人工土壌粒子５０として、（ａ）細孔４を有する複数のフィラー３を造粒してなる多孔質体１０ａを基部１０として有する第一人工土壌粒子５０ａと、（ｂ）繊維１を集合してなる繊維塊状体１０ｂを基部１０として有する第二人工土壌粒子５０ｂと、を含む。【選択図】図３
