PROBLEM TO BE SOLVED: To provide granular culture soil suitable for growing plants in planters by mixing CMC and a porous granular culture soil composed of inorganic components which is excellent in air flow property but poor in water retentivity to improve water retentivity of the soil without spoiling air flow property.SOLUTION: A water retentive granular culture soil of the invention comprises a granular culture soil made by uniformly mixing 8.9 L of Akadama soil 1, 1.0 L of Kanuma soil 2, and 0.7 L of perlite 3, all of which were screened to be 2-5 mm in diameter, and 14 g of carboxymethylcellulose particles of which particle diameter is 0.2-1.0 mm. The carboxymethylcellulose dissolves in watered water and swells to form lumpy carboxymethylcellulose 4, which increases the water retentivity of the granular culture soil without spoiling the air flow properties of the culture soil to enhance plant growth.SELECTED DRAWING: Figure 19COPYRIGHT: (C)2017,JPO&INPIT【課題】通気性には優れているが保水性が乏しい無機質成分の多孔質粒状培養土にCMCを混合することで通気性を損なうことなく保水性を向上させ、プランターによる植物の栽培に適した粒状培養土を提供する。【解決手段】粒径2~5mmに選別した赤玉土1、鹿沼土2及びパーライト3を、赤玉土1が8.9L、鹿沼土2が1.0L、パーライト3が0.7Lの割合で均一に混合した粒状の培養土に対して、粒径0.2~1.0mmのカルボキシメチルセルロースの顆粒を14g混合して成り、プランターでの植物栽培において、水遣りの水で溶けて膨潤した塊状のカルボキシメチルセルロース4が粒状の培養土の通気性を損なわずに保水性を向上させ、植物を大きく成長させる。【選択図】 図19
