There is an hour in Watertown when the brick along Arsenal Street goes copper and the grass in front of it looks greener than it has any right to. K&E Landscaping Inc. is often finishing up around then — last strip mowed, beds edged, clippings swept off the sidewalk and put back on the lawn where they belong. Mulch goes down in May, leaves come out in November, and in between it is the steady weekly rhythm that keeps a yard from getting away from anyone. Even a modest lot near Coolidge Square can look settled and deliberate when the lines are straight and the beds hold their shape. Lawn care in Watertown and the communities around it.