PROBLEM TO BE SOLVED: To facilitate the discharging and cleaning work of fertilizer remaining in a long pipe-shaped air tank 34 for sending compressed air flow to a hose joint of a fertilizing apparatus. SOLUTION: The objective fertilizing apparatus placed at the rear part of a traveling machine body 1 having a seedling transplanting apparatus at the back is composed of a feeding pipe to supply fertilizer to a planting part of the seedling transplanting apparatus, a hose joint connecting the feeding pipe at the rear end, a fertilizer-storage hopper connected to the upper face of the middle part of the hose joint and an air tank 34 having a round pipe form and supplying fertilizer-transporting air flow through a connection pipe 56 attached to the tip end of the hose joint. A plurality of long cleaning holes 125 are opened on the bottom side of the outer circumferential wall of the air tank 34 along the longitudinal direction of the tank 34 and the cleaning holes 125 are closed with detachable lids 126 made of a semi-rigid synthetic resin.
