Spring arrives in the Saw Mill valley well before it climbs the ridges. Down on the Elmsford flats the grass greens early, while up in Hartsdale and Edgemont the shade is still holding out a few more weeks. White Plains Lawn Care Service reads Greenburgh that way, block by block, and sets the mowing calendar to what the ground is actually doing rather than what the date says. Mow, trim, edge, blow the clippings off the bluestone; open the beds in April and put the yard to bed in November. Nothing elaborate — done weekly, done on the day it was promised. A straight edge along a front walk is a small thing, and it changes how an entire yard looks from the street.