Situated within the West Conservatory complex at Longwood Gardens, the greenhouse containing this 3,000-square-foot garden was originally built by Pierre du Pont in 1921 after Longwood’s purchase in 1906 and was known as the Geographic House. The structure was initially equipped with the latest technology in heat, water, and power, with support systems hidden in tunnels so as not to detract from the grandeur of the glass-covered peristyle and surrounding rooms. Unusually, du Pont used the greenhouse to grow peaches and nectarines rather than the customary exotic tropical foliage then in fashion, and as a result, the greenhouse was said to have resembled a “floral sun parlour.”
The West Coast landscape architect Isabelle Greene, known for her expertise in Mediterranean plants, was invited to create a dry-climate display in 1989. The garden, which was fashioned over eighteen months, would become known as the Silver Garden and was in part an experiment to test whether xerophytes could survive in hothouse conditions. The garden is characteristic of Greene’s other work, incorporating many of the silver-leafed plants she was accustomed to using in her California designs. Similarly, all the plants, including the dragon-tree, old-man cactus, century-plant, and olive, showed an evolutionary adaptation to arid climates. The monochromatic design comprises plants of pale green, gray, and silvery-blue tones, which are interspersed with rock outcroppings and gently bisected by a meandering, blue-gray slate pathway, the full composition resembling a dry streambed as found in a desert. At night, the moonlight reflected off the foliage draws the plants into the fore, while the spartan iron truss-work of the greenhouse fades into the background. Longwood Gardens was listed in the National Register of Historic Places in 1972.