It is commonly said that landscape architects are pros with structure and amateurs when it comes to plants. The cliché about horticulturists and nurserymen is that they’re so busy focusing on individual species, they lose sight of the big picture. Judy Murphy, though, is that rare garden professional who sees it both ways. Trained as a landscape architect, she can whip up a site plan for even the slipperiest slope. But she’s also a seasoned nurserywoman who waxes poetic about the latest cultivars and declares chartreuse foliage the ultimate neutral.