Aiden Matranga's 20th-minute strike gave Grove an interval lead, but second-placed Carlton produced an inspired spell after the break which turned the game on its head.
The visitors levelled on 53 minutes through Terry Hawkridge and romped away with further goals by Nick Hall (72), Hawkridge (78) and Massiah McDonald's late double (81 and 85).
Matt Haddrell fired the parting shot from the penalty spot in the 90th minute with his first goal for the club since returning from Congleton in November.
Ward said: "It is difficult to put my finger on what went wrong. We were brilliant in the first half and could have had another couple of goals, but awful in the second.
"We were solid and did not look like conceding, but they were lifted by their equaliser. We then sat deep and could not get hold of the ball and they had a spell when we were not at the races."