On an August day the breeze that reaches Deer Park has come up off the Great South Bay, salt-soft and heavy, and the grass grows thick in it. Paul LI Landscaping mows through that humidity, working the yards south toward the parkways where sprinklers tick in the side lots and the pavement gives back the day's heat until dark. Trimming around fence posts and mailbox pipes, edging where the drive meets the turf, blowing the walk clear — the small finishing moves that separate a cut lawn from a finished one. When the season turns and the leaves come down over the same properties, the cleanup goes just as thoroughly. Long Island summers are short and loud; a well-kept yard is how a house enjoys them.