A cultivator attachment is mounted to the side of a tractor and includes an outwardly projecting boom assembly with first and second boom sections. The boom sections telescope and a cultivator head with a rotating cultivator member is connected to the free end of the second boom section. A first hydraulic cylinder raises and lowers the boom assembly while a second such cylinder extends and retracts the second boom section to move the cultivator head inwardly toward and outwardly away from the tractor to avoid obstacles in its path. A hydraulic motor on the head rotates the cultivator member about its axis. A side tilt mechanism located at the free end of the second boom section tilts the axis of the cultivator member in the plane of the boom assembly to direct the discharge of material from the cultivator head toward or away from the tractor during cultivation. A boom assembly attachment mechanism permits rotation of the boom assembly about its longitudinal axis to orbit the cultivator head about the boom axis to control the forward and rearward discharge of material from the cultivator member as desired. In the event the boom assembly or cultivator head hits a solid object, a link shock absorber operates to absorb the energy of impact. A separate hydraulic fluid tank is included in the hydraulic circuit for the cultivator head motor and this tank forms an integral part of the mounting system for the attachment.