You know it's time to cut your grass when...
You look out your window one morning to find a National Geographic photographer in your yard, crouching in the tall grass...
You noticed even the dandelions stopped bothered to grow surrounded by such steep competition...
Your peeping tom neighbor no longer bothers with binoculars from across the street; he simply hides in your grass three feet from your window...
You see a group of bird watchers pitching a tent in your yard and setting up tripods at dawn...
One day you decide to finally cut the grass, but can no longer see where you left the lawnmower.