April along the Alewife Brook is a loud sort of green — marsh grass rising, parkway traffic humming, everything waking at once off Rindge Avenue. TT Landscaping Corp. starts the season there with spring cleanups, raking the winter mat out of the turf, the first mow, and fresh mulch in the beds. Through summer it becomes a steady rotation of mowing, edging and trimming, held to a schedule so no lawn gets away from itself. The finish shows at the property line, where the grass stops in one straight line against the walk. North Cambridge outward through the rest of the city and into the neighboring towns is the range.