The glider was winch launched to a height of 900 feet above the ground. The pilot was unable to find any strong lift, and when the glider had descended to 600 feet the pilot rejoined the circuit for landing. Some sink was experienced on the downwind leg and the glider was only about 200 feet above the ground when the base turn was made. During the turn onto final approach, the right wing of the glider struck the ground. The aircraft swung sharply to the right and subsequently landed heavily. There was no other traffic in the area and the pilot could have modified his circuit and landed on a cross-strip. It was likely that he had attempted to land the aircraft close to the winch launch cable to facilitate the next flight.