To provide a method for oxidizing and sterilizing soil for agriculture and horticulture with ozone, comprising first making soil without using a synthetic chemical agent, returning to the original point of the soil, finely crushing the soil, enough contact and oxidation of the fine soil mass with ozone gas to sterilize the soil, making the pure soil free from pathogenic bacteria, and mixing the soil with carefully selected organic fertilizers to obtain the original organic soil for agriculture and horticulture, and to provide an apparatus therefor.

In the present invention, the soil itself is oxidized and sterilized with ozone without using a synthetic agrochemical from the start of making the soil. Therefor, working farmers or agricultural or horticultural products start sterilization by simple ozone oxidation not related to synthetic chemicals from the first step for making soil to make the aseptic soil. A compost sterilized at higher temperature than 80C for a long time with fermentation heat is used as an initial manure to form the agricultural soil. A true organic culture not related to agrochemicals appears for farmers and agricultural products. In addition, the insertion or spray of ozone water prepared by dissolving ozone in water is effective for upland field highly containing water and for rice paddies. Since both a gas and a liquid can be used, the method has excellent characteristics on the employment of the ozone.