Saturday morning at Hamilton Park: the fountain running, dogs already at the run, and the grass along the iron fence asking for a line to be drawn. Matt's Landscaping cuts and edges the yards around that stretch of downtown Jersey City — weekly mowing, string trimming to the fence posts and the tree pits, beds cleaned out at both ends of the year. An edge is the whole difference between a lawn and a patch of grass, and it costs two extra minutes. Neighbors register that trimmed line long before they notice anything else about a property. So that is where the time goes.