I'm in Northern Virginia. I cut with the front tip of the blade at 3.75 inches and the back edge of the blade at 4.0 inches. That's our standard cut height. On certain lawns we cut lower... if the owner asks for it... but I try to dissuade them. I cut at that height because it keeps the lawn green throughout the season - no summer burn, it keeps the weeds out and the lawn healthy, it keeps the mowers running every week, and it keeps my bank account growing.