Abstract: A mulching mower has at least one generally enclosed cutting chamber in which a rotatable cutting blade is carried for rotation in a generally horizontal cutting plane. A sidewall defines the circumferential boundary of the cutting chamber and the grass clippings exit the cutting chamber through an open bottom side thereof. An attachment is abutted against the bottom of the blade and is secured thereto by the same attachment bolt that holds the blade to the engine drive shaft to provide a plurality of winglets that rotate in unison with the blade. The winglets include forwardly inclined grass deflecting surfaces that extend over an inner portion of each blade half and help evacuate the grass clippings from the cutting chamber. The tip portions of the blade may also be cut away or chamfered in the range of 7.degree.-15.degree. relative to a square radial tip configuration.