A mowing device for plants includes at least one rotor with a first rotation axis, and at least one blade which is driven in rotation by the rotor, in which the blade is attached to a blade holder during normal operation. By a blade pivot pin or shaft that is situated at a radial distance from the first rotation axis. This allows the blade to be freely rotatable through at least a predetermined angle. The blade pin can be displaced radially inwards. The blade holder is connected to the rotor about a latent dedicated second rotation axis； and the first and second rotation axes and the blade pivot pin determine a triangle in a plane of projection at right angles to the first rotation axis.
