A material collection system sensor assembly for a material collection system including a collection container having a clipping receiving chamber and at least one wall with a generally rigid portion and a chute inlet defined in the generally rigid portion. The sensor assembly includes a capacitive sensor positioned on the generally rigid portion of an external side of the wall. The capacitive sensor creates an electric field that extends into the clipping receiving chamber. A microcontroller is associated with the sensor and at least one indicator. The microcontroller is configured to activate at least one indicator when clippings within the clippings chamber are consistently within the electric field and thereby trigger the capacitive sensor.