Abstract: Interchangeable lawn dethatcher means for a rotary cultivator with removably affixed cultivating tines. The lawn dethatcher means includes a first rigid member and second rigid member each removably affixed to the rotary cultivator in place of the cultivating tines, and a plurality of rigid dethatchment tines removeably affixed in helical array to the first and second rigid members in mirror image relationship, respectively, each dethatchment tine being received through the rigid members and arrestingly clamped at the midpoint of the tine and each tine having a bent portion at each of its ends disposed in the direction opposite the intended direction of tine rotation. The lawn dethatcher means are supported at their outermost points from the rotary cultivator by independently rotatable utility wheels sized to permit the ends of the dethatchment tines to extent below the point of contact of the wheels with the lawn and thereby into contact with lawn thatch.