Longer than most (St. Augustine). Many people cut too short making the grass susceptible to burn and disease. It may look sharper and cleaner, but it must be feed chemicals to look healthy. Kind of like giving it dough nuts. It gives the grass energy, but it doesn't make it healthy. I've seen too many chemical lawns go from looking very nice to looking like crap once you stop feeding them. It's sad.
Christian Culture Warrior