It was in 1980, while hunting for a weekend hideaway, that Renny fell for the 18th-century stone farmhouse, nestled among dogwoods and big, plump mounds of box, which he glimpsed across a rushing stream. “I had to have it,” he quietly admits, radiating his love of the place while also recalling the apprehension he felt at the scope of the challenge he’d taken on. Since then, the woods have been cleared of debris and planted with bulbs, native shrubs, flowering trees, and ground covers; ponds have been scooped from the brook; perennial borders and a pool garden have emerged amid former fields. Walks have been cut to spots where Renny finds homes for follies, gazebos, and statues that once figured in his Philadelphia Flower Show displays. “I can’t throw anything out,” he says.