The pilot reported that during the landing approach to the grass runway he had ample time to observe the runway surface and the turf appeared smooth and even. He continued the approach and executed a soft field landing. While on the landing roll, he noticed a puddle of water ahead. He commanded full up elevator and attempted to "jump" the puddle, but the airplane had already slowed below flight speed. The main landing gear of the tailwheel equipped airplane struck the standing water that was about 3 inches deep, and hidden by the grass. The airplane slowed abruptly and the airplane subsequently nosed-over resulting in substantial damage to the vertical tail, and right wing strut. The pilot reported that there were no mechanical malfunctions of the airplane.