You really should be getting some contact with the ground, but like CanCaddy said, it shouldn't be so much that it ruins your shot (known as hitting the ball fat)
I'm guessing there are a lot of different causes for hitting the ball fat, but I recommend you really focus on keeping your eyes on the ball the whole way through the swing. It sounds simple but I sometimes have to remind myself to watch the ball, and my ballstriking consistency goes back to normal.