The present invention relates to a sowing heart monitoring device for connection to a sowing heart (3') and for monitoring the sowing heart (3'), having a line scan camera (21) with a detection device (E), a housing (20) which can be fastened to the sowing heart (3') and is intended to accommodate the line scan camera (21), and a radiation source (22) for generating electromagnetic waves which can be detected by the line scan camera (21) and have a radiation direction (S), wherein the sowing heart monitoring device (12) is designed in such a manner that electromagnetic waves generated by the radiation source (22) can be detected by the line scan camera (21) after reflection at a reflection surface (13) of a rotatable sowing disc (9) of the sowing heart (3') and can be evaluated by an evaluation unit. The present invention also relates to a sowing heart and to a single grain sowing machine.