September light along the Concord River, where it runs its last mile to meet the Merrimack, is the best light Lowell gets — long, warm and generous to a freshly cut lawn. Rolmack's Landscape & Construction keeps yards in that condition right through the growing months with weekly mowing, trimming and crisp edging along drives and walks. The spring visit is the heavy one: raking out whatever the plows threw, cutting beds back, giving the turf air after five months under snow. Then the year settles into rhythm, week after week, until the leaves come down and a final cleanup carries them off. What's left behind should look effortless — that is the trick, and the point.