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St. Jude Medical -- Restoration and Prairie Gardens on a Corporate Site Page 3 of 7 instance, does not extend as far north as St. Paul. However, this plant has such a strong association with prairies that it fits well in the garden areas. o Bedding plants and bulbs. Few prairie flowers bloom in early spring. In Minnesota, it is late May and early June before the puccoon, prairie phlox, and butterfly weed begin their display. Narcissus and Phlox subulata (creeping phlox) are used in some of the garden areas to provide early spring color. 2. Framing and contrasting. Sweeps of turf and a formal hedge of Ribes alpinum (alpine currant) are employed for framing and contrasting. The hedge begins at the street entrance and it separates the prairie from the entrance garden. This separation helps people compartmentalize the scene -- you first see the formal prairie garden and in the distance the prairie and savanna. The turf not only frames but provides a striking contrast to the formal beds or the unmowed prairie. 3. Geometric plantings. Geometry and straight lines seem hypocritical in a naturalistic planting. Yet in these prairie gardens they provide a sense of order. Some of the beds are strict rectangles with a single species or two planted soldier -like in rows and columns. When grasses are used in this format, they soften the harsh lines. Liatris and Rudbeckia cultivars blocked in this manner are bold and dramatic in bloom. There is nothing prairie -like in these geometric plantings. They represent the extreme end of a continuum from formal garden to naturalized garden to restoration.. The same species are repeated in more natural beds which have curving lines, more informal spacing, and a mix of trees, shrubs, and herbaceous materials. In establishing the formal areas, it was important to have the gardens presentable as soon as possible. Therefore, containerized plants were used, not seeds and seedlings. Additional top soil was brought in for the gardens. Some of this was rich soil from the low areas and had been stockpiled during construction. Boulders were placed to enhance the design and after planting a shredded bark mulch was applied to reduce weed growth and conserve moisture. The installation was done by the design company's landscape crew. This crew also maintains the gardens. The grasses and flower seedheads are not cut in the fall so they provide interest during the winter season. Spring clean-up includes pruning and cutting back the herbaceous plants. From May through August, the crew visits the site twice a month for weeding. The plants in the gardens are drought tolerant. Watering was done the first year to ensure successful establishment but is no longer necessary. No fertilizer is used in the gardens. Nutrients in the form of dead herbaceous material are not being returned to the soil but the gardens started with a rich topsoil, receive nutrients from decomposing bark mulch, and most of the species planted flourish in infertile soil. THE NATURAL AREAS The natural areas on the site required varying levels of intervention. An oak woodland that covers a hillside has been left untouched. It is heavy with underbrush including Rhamnus cathartica (common buckthorn). Hagstrom acknowledges that the woodland needs a management plan. The remnant oak savanna had several old oaks which were pruned to remove dead limbs. A small area (about 1000 square feet) in the savanna had a ground cover of native species including Koeleria cristata (June grass) and other native grasses. This patch was weeded to remove non - native species; no seeds or plants were added. The ground cover for the rest of the oak savanna was prepared and seeded like the prairie. The largest prairie area is in front of the building and merges into the savanna. The prairie areas are not all contiguous and include some fairly narrow swatches. For example, three parking lot islands are from ten to twenty feet wide and up to 280 feet long. Thus, you do not have the feeling of being on a vast expanse of prairie. Instead, it is more akin to a prairie pocket which might have been http: / /www.hort. agri. umn .edu /h5015 /96papers /gayner.htm 2/22/01 • • •