Mulching machine for laying a covering cloth over a ground to be covered, said mulching machine comprising: - a support frame susceptible of advancing on the ground along an advancement direction; - at least one reel of a covering cloth intended to be laid on the ground, said reel being rotatably associated with said support frame by means of support means; - laying means mechanically associated with said support frame, interposed between said reel and the ground, and adapted to unroll, from said reel, at least one strip of said covering cloth and to lay said strip on the ground; - earthing up means mechanically associated with said support frame and adapted to at least partially bury the strip of said covering cloth laid on the ground; said earthing up means comprising a roller rotatably associated with said support frame and provided with a rotation axis placed substantially parallel to the ground and orthogonal to said advancement direction, and a plurality of teeth mechanically connected to said roller and projecting outside the latter radially with respect to said rotation axis; - first movement means, placed to mechanically connect between said support frame and said roller, in order to move said roller between an interference position, in which said roller is in a distal position with respect to said support frame and at least one of said teeth is susceptible of intercepting the ground, and a non-interference position, in which said roller is in a proximal position with respect to said support frame and said teeth are susceptible of not intercepting the ground; - second movement means, mechanically associated with said roller, in order to rotate said roller around said rotation axis; said mulching machine being characterized in that said second movement means are adapted to rotate said roller alternately in a first rotation sense and in a second rotation sense, opposite with respect to said first rotation sense; said mulching machine also comprising a logic control unit operatively connected to said first and second movement means (13, 14) and configured for driving said second movement means to rotate said roller in said opposite rotation senses (V1, V2), with said roller placed in said interference position, in order to earth up two opposite ends of said strip with the teeth of said earthing up means rotating in said two rotation senses (V1, V2). - a support frame susceptible of advancing on the ground along an advancement direction; - at least one reel of a covering cloth intended to be laid on the ground, said reel being rotatably associated with said support frame by means of support means; - laying means mechanically associated with said support frame, interposed between said reel and the ground, and adapted to unroll, from said reel, at least one strip of said covering cloth and to lay said strip on the ground; - earthing up means mechanically associated with said support frame and adapted to at least partially bury the strip of said covering cloth laid on the ground; said earthing up means comprising a roller rotatably associated with said support frame and provided with a rotation axis placed substantially parallel to the ground and orthogonal to said advancement direction, and a plurality of teeth mechanically connected to said roller and projecting outside the latter radially with respect to said rotation axis; - first movement means, placed to mechanically connect between said support frame and said roller, in order to move said roller between an interference position, in which said roller is in a distal position with respect to said support frame and at least one of said teeth is susceptible of intercepting the ground, and a non-interference position, in which said roller is in a proximal position with respect to said support frame and said teeth are susceptible of not intercepting the ground; - second movement means, mechanically associated with said roller, in order to rotate said roller around said rotation axis; said mulching machine being characterized in that said second movement means are adapted to rotate said roller alternately in a first rotation sense and in a second rotation sense, opposite with respect to said first rotation sense; said mulching machine also comprising a logic control unit operatively connected to said first and second movement means (13, 14) and configured for driving said second movement means to rotate said roller in said opposite rotation senses (V1, V2), with said roller placed in said interference position, in order to earth up two opposite ends of said strip with the teeth of said earthing up means rotating in said two rotation senses (V1, V2). said mulching machine being characterized in that said second movement means are adapted to rotate said roller alternately in a first rotation sense and in a second rotation sense, opposite with respect to said first rotation sense; said mulching machine also comprising a logic control unit operatively connected to said first and second movement means (13, 14) and configured for driving said second movement means to rotate said roller in said opposite rotation senses (V1, V2), with said roller placed in said interference position, in order to earth up two opposite ends of said strip with the teeth of said earthing up means rotating in said two rotation senses (V1, V2).