Spring reaches the streets above the mills late and then all at once — one week grey and sanded, the next the whole hill is greening. Petit Landscaping Inc handles those in-town yards, small and terraced and close together: mowing, string trimming, edging along the walks, and hauling out what winter left behind. Working tight city lots means the mower lines have to be right the first time, because there is no room to hide a pass. A cleaned-up dooryard changes how a whole block reads from the sidewalk. Biddeford, block by block, and the towns adjoining.