Garden Center Magazine : Current Issues Green roofs take root

Garden centers are a natural place to find green roof technology at work, according to Dr. Robert Berghage, of the Center for Green Roof Research at Penn State University, State College, Pa. Not only because garden center owners have an innate knowledge of plants, but also because there’s already product on hand. This new “green” frontier shouldn’t be too much of a challenge for garden centers. Horticulture businesses are presumably good at growing plants, understand their needs and have a good grasp of which growing media works best in containers. “A typical green roof is really just a big, shallow outdoor container with a rock garden in it,” Berghage said. “That being said, the green roof is unique in a number of ways that may pose interesting challenges.” First, the media is different. “We use an inorganic, aggregate-based media in a green roof rather than the organic potting soil most nursery growers are used to,” Berghage said. “This is because the roof will be in place for many years and an organic potting soil will decompose over that period.”"