220 Perennial Garden. Center. Project Update

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1 3 Center Project Update 220 Perennial Garden The landscape design resembles the relaxed and natural New Wave Planting Style. The layout is less controlled and geometric than traditional gardens. The landscape will evolve into an idealized version of nature and support biodiversity with an integrated planting palette. Flowering perennials, ornamental grasses and deciduous shrubs will harmonize in the landscape to provide a constantly changing range of colors, textures, and form. Large masses of complementary plants will be grouped together to address the scale and render a powerful aesthetic. In the winter months the garden will continue to provide structure to the landscape. Ornamental grasses, crab apple trees with persistent fruit, and perennial seed heads will specifically stand out through the white snow. Lawn, stone and concrete paths will provide visitors and employees an opportunity to experience the garden up close. Small seating and picnic areas are scattered about providing destinations in the landscape. Existing and proposed trees will render shade and vertical scale to the environment. The design will thoughtfully group plants in stunning combinations that look and grow well together. Damon Farber Associates

2 2 220 Perennial Gardens Design Sustainable Stormwater Approach A sustainable approach towards stormwater management involves a wide variety of techniques, each of which aims to increase the absorption of runoff, recharge groundwater and reduce or eliminate pollutants. The new management techniques employed for the building 220 landscape, new visitor parking lot, and access road include two infiltration basins. These basins will handle surface runoff allowing the stormwater to be filtered and infiltrated into the ground at its source. The infiltration of stormwater on site will minimize water quality degradation, erosion, and flooding, as well as minimize the expense associated with artificial stormwater conveyance systems (pipes, sewers, etc.). The infiltration will effectively filter and remove pollutants from the stormwater. Vegetated strips and plants within the basins will be highly effective at removing many of the toxins and pollutants that can be carried in stormwater. Irrigation In addition to cleaning, detaining and infiltrating stormwater, the basins also recharge groundwater levels. This is important, as the garden s irrigation supply is from groundwater. A pump in the northeast corner of the garden will pull groundwater from hundreds of feet below ground. Literally hundreds of irrigation rotor and pop-up spray heads will work to maintain proper hydration for the gardens. Pathways Two types of paths bisect the landscape. Concrete paths meander through the gardens along the north and a crushed granite path meanders along the south. The system will afford visitors and 3M ers easy access to a combined pathway system extending over 1.5 miles. Visitor Parking The new visitor parking lot has 66 parking stalls and is accessed from 11th Street. Once in operation, visitors will utilize this lot and experience the perennial gardens close up as they make their way to building 220. Soils All planting beds have received a 12 minimum thickness of imported premium topsoil. The planting soil was specifically designed to render optimal growing conditions for the mixed perennial garden. The selected planting soil specifications include: 7.5% Organic Matter 41.2% Sand 24.6% Silt 23.5% Clay 6.9 PH 3Update Damon Farber Associates

3 3 8th Street 11th Street 229 Parking Sidewalk 221 Community Plaza 220 Visitor Parking Drop-Off 222 Perennial Gardens Lawn Path Interstate 94 Landscape Illustration

4 4 Plants The gardens are comprised of more than forty varieties of flowering perennials, and twenty varieties of ornamental grasses. Seven shrub species are used to a lesser extent in the perennial gardens. All plants are spaced closely together and expected to fully fill in the garden beds. A smaller mix of shade and ornamental trees will add vertical scale to the gardens. The landscape will embody an ever evolving combination of form, texture, color, scent, and contrast. Spring flowering crab apple trees will deliver the first color of the season. April will also bring the first signs of life in the garden, as daylilies, sedums, and other early to emerge perennials poke up through the mulch. By mid-summer the garden s soil temperature The landscape will evolve into an idealized version of nature and support biodiversity with an integrated planting palette. combined with higher average nightly temperatures will allow plants such as liatris, miscanthus grasses, and Rudbeckia to bloom. Deep-rooted ornamental grasses will aid with stormwater infiltration and begin to steal the show come September. Bands of trees are intended to provide vertical definition and filtered shade along the south edge of the visitor parking lot and the lobby of 220. Along the south facade of 220, Renaissance Reflection Birch trees will form a loose collection of shade trees. This variety of Paper Birch has a rapid growth rate, striking white bark, and is heat tolerant. The landscape of Paper Birch planted within a bed of flowering perennials should provide a dramatic reflected image within the lobby of 220. Red flowering Monarda, pictured below left, along with red blooming day lilies are used extensively in the gardens at critical locations to render 3M s corporate color in the gardens. Fall will bring additional red to the landscape as the dozen or so Maple trees turn a brilliant red later in the season. Native Plants The garden relies on a large variety of species for diversity and interest. Native plants are those found naturally in the Minnesota region. In addition many other well-adapted plants are employed that need little or no fertilizers to thrive in our climate. Native Plants Include: Rhus typhina, Staghorn Sumac Diervilla lonicera, Dwarf Bush Honeysuckle Quercus bicolor, Swamp White Oak Asclepias tuberosa, Butterfly Flower Echinacea purpurea, Purple Coneflower Eupatorium maculatum, Joe Pye Weed Panicum virgatum, Switch Grass Schizachyrium scoparius, Little Bluestem Sorghastrum nutans, Indian Grass Sporobolus heterolepis, Prairie Drop Seed Liatris pycnostachya, Blazing Star 3Update Damon Farber Associates

5 Progress 5 Progress Report The old water feature is long since removed, and the cooperative weather has extended the planting season well into late Fall. Earlier in the summer some existing trees were removed to make way for the new parking lot and entry drive. Remaining evergreen trees were pruned-up to improve air flow, visibility and for their own health. The landscape installation south of 220 is expected to reach 80% completion prior to freeze up. The installing contractors will continue planting as long as the ground is not frozen. Approximately 21,500 perennials, 800 shrubs, and 40 trees have been installed as of 11/11/11. Roadway and parking lot lights have been installed and bollard lights are currently begin installed that will illuminate the concrete pathways to building 220. Sod installation has begun and will continue weather permitting. If the weather continues to cooperate the contractors may be able to begin installation of the crushed granite path in the coming week. What to Expect Next Summer Early next year the last 10-20% of planting, pathway connections, furnishings, and the final lift of pavement will be completed. The design team will perform final inspections of the work upon substantial completion. At that time punch list items will be noted for correction and when complete the gardens will be open for all to enjoy! Keep in mind the old saying that goes with perennials- first year sleeping, second year creeping, third year leaping!. In other words the gardens will not reach full maturity until the summer of Design Numbers Shade Trees 47 Ornamental Trees 94 Evergreen Shrubs 859 Deciduous Shrubs 17,864 Flowering Perennials 7,968 Ornamental Grasses Over 25,800 Total Perennials 1,366 of 5 wide crushed granite path 1,993 of 6 wide concrete sidewalk Over 1.5 miles of walking surface when linked with existing trails to the east

6 6 Partial Plant Palette Achillea Moonshine Yarrow, Moonshine Allium tanguticum Summer Beauty Allium, Summer Beauty Aruncus aethusifolius Goat s Beard, Dwarf Echinacea x Evan Saul Coneflower, Big Sky Sundown Coreopsis Jethro Tull Coreopsis, Jethro Tull Echinacea purpurea Rubinstern Coneflower, Ruby Star Echinacea purpurea White Swan Coneflower, White Swan Gaillardia aristata Arizona Sun Blanket Flower Helenium Mardi Gras Sneezeweed Hemerocallis Barbary Corsair Daylilly, Barbary Corsair 3Update Damon Farber Associates

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