The Rippowam runs low and clear past Scalzi Park in late August, and the ballfields beside it hold the last of the evening light. Lucky Lawn keeps grass on the streets around there and out through the middle of the city — mowing, trimming, edging, fertilizing, seeding and cleanups, week after week, until a yard stops needing to be thought about. Good turf is mostly patience and timing: cut high through the heat, feed as the nights cool, get seed down while the soil is still warm underfoot. The sound a mower makes on a lawn that has finally thickened is lower and softer, the note of grass that has closed ranks. That's the whole ambition, honestly.