Abstract: A vertical, substantially funnel-shaped feed chute attaches to the top of the mower deck of a rotary lawn mower. The bottom opening of the feed chute corresponds with an aperture in the mower deck. The rotary mower is further adapted by reversing a double-edged cutting blade to reverse the air flow characteristics from upward to downward. Garden debris for mulching is inserted into the mouth of the feed chute and is drawn into contact with the cutting blades by gravity and by the movement of air drawn down through the feed chute by the aerodynamic wing on the cutting blade.