PROBLEM TO BE SOLVED: To prevent seed rices which are sown in a seedling raising box from being overlapped vertically for enhancing sowing degree, and make seedling length of a seedling to be transplanted suitable in transplantation in a transplanter.SOLUTION: A culture soil comprising a silicic acid component, in which a nitrogen component is 0.25 g/kg or lower and whose apparent specific gravity is 0.8 or lower, is packed in a bed-soil state in a seedling raising box 2, then seed rices are sown in an almost whole surface of the seedling raising box 2 so that the seed rices are not overlapped vertically, then after sowing, a culture soil comprising 0.25 g/kg or higher of a nitrogen component and a compost of up to 0.4 g/kg, and comprising the surplus compost of exceeding 0.4 g/kg which is a granular compost subjected to coating, covers the seed rices. The seed rices are grown over 11-18 days until the seed rices grow to a seedling length of 10-12 cm being an intermediate seedling length of nursling seedlings and young seedlings.SELECTED DRAWING: Figure 2
