A floating swathgate for a cutting and conditioning header for a frame-supported tractor in which the angular attitude of the swathgate relative to an airborne stream of crop material being ejected from conditioner apparatus is varied as the header moves vertically with respect to the tractor to optimally direct the crop material toward a rearwardly disposed crop merger conveyor. As the header moves vertically, changes in the angular attitude of the swathgate direct the airborne crop material to generally the same location on the merger conveyor to minimize crop losses that typically occur with a fixed swathgate when the crop trajectory varies directly with the header vertical movement.