Come July, Shedd Park smells like cut grass until dark, and the neighborhoods around it keep to the same standard. Marty's Landscaping Inc mows, trims and edges yards through that long green stretch of the Lowell year, when a lawn asks for attention every single week or lets you know about it. The season opens with a cleanup — winter sand raked out, beds cut back, everything let into the light — and closes in November with the last of the oak leaves off the turf. In between it is simple and exacting: straight lines, clean corners, nothing left in the street. A yard the family can walk out into barefoot is the whole ambition.