Abstract: It is intended to provide an apparatus for producing seedlings and a method therefor whereby, in producing grafted seedlings of fruit vegetables, a process from the culture of their stocks (rootstocks and scions) to welding after the grafting can be accomplished in a consistent process at low cost. Rootstocks and scions are nursed on multi-staged seedling culture shelves 3 installed in a closed-type structure surrounded by light-interceptive thermally insulating walls, and then these rootstocks and scions are joined to each other to produce grafted seedlings 8. Then, these grafted seedlings 8 are placed on shelf boards 3a of the seedling culture shelves and covered with a light-transmitting shield 9 provided with vent holes 15, and light of a predetermined luminous intensity is projected onto these grafted seedlings from fluorescent lamps 5 through the light-transmitting shield to weld the grafted seedlings 8.