By mid-July the crepe myrtles along Douglasville sidewalks are throwing color, and the yards that look best are the ones where somebody has been working the beds since March. Marshalls Green Thumb LLC lives on that side of the job — bed maintenance and weeding, mulch, plantings, shrub trimming and shaping — with mowing, edging and cleanups holding the frame around it all. Growing things is a slow argument you win in stages: cut here, feed there, wait a week, come back. The payoff arrives on somebody's front walk in the middle of summer, exactly where everyone can see it. Douglasville and out toward Villa Rica make up the service area.