A sowing heart monitoring apparatus for connection to a sowing heart and for monitoring of the sowing heart with a line camera with one detection direction, a housing which can be attached to the sowing heart for accommodating the line camera and a radiation source for generating electromagnetic waves which can be detected by the line camera with one radiation direction. The sowing heart monitoring apparatus is made such that electromagnetic waves which have been generated by the radiation source can be detected by the line camera after reflection on one reflection surface of a rotating sowing disc of the sowing heart and can be evaluated by an evaluation unit. The invention also relates to a sowing heart and a single-seed drill.