For a few weeks each April the hills on the west edge of the valley go orange with poppies, and every yard in Lancaster seems to want to answer with green. Miller's Green Gardening meets that season with the mower deck set right and the trimmer already running — spring growth here is fast, generous and easy to lose track of. A weekly cut through April and May keeps a lawn even instead of lumpy, and a run of the edger along the walk gives the whole yard its outline back. Clippings go with the truck; the driveway gets swept. When the poppies fade in May, the lawn is the thing still holding the color.