Our proposal will make Constitution Gardens an active part of the urban ecology of Washington, D.C. The site will be rebuilt as an aesthetic ecology by carefully refining the scale, shape, and function of each landscape component—landform, soils, plant materials, water flows, paving. Regenerated soils and a consistent drainage layer will encourage a rich biology in an integrated environment.
The lake will be transformed by a modified profile and a new aquatic shelf planted with herbaceous aquatic vegetation. These components will work together to reduce storm-water impacts, create a source of reusable water, increase habitat potential, and aesthetically engage the adjacent buildings, the Lincoln Reflecting Pool, and the Tidal Basin.
Subtle modifications to the lake’s appearance—a reflecting basin at its east end and two aeration circles—will add to its beauty as well as will improve its ecological function and performance. The depth of the reflecting basin makes it adaptable to a range of activities— ice skating in the winter, model boating in the summer. Aeration adds an unexpected visual element while improving water circulation.
Diverse Plant Ecologies
Rolling lawn and canopy trees define the character of Constitution Gardens. Our proposal will amplify that character by diversifying the understory of both lawn and wooded areas and by implementing a planting strategy that is seasonally dynamic in color and form.
Lawns and Meadows will be composed of a mix of low-growing, drought-tolerant grass species and small flowering perennials that can be mown regularly or allowed to grow and flower. The woodland understory will be a mix of sturdy ground cover and fern species inter-planted with bulbs, requiring only a single annual cut back for maintenance.
In the original design for Constitution Gardens, white and pink flowering plants were intended to create the effect of painterly strokes; the Flowering Upland and Lowland Gardens of the re-design will create this effect with a wider variety of species choreographed for successive waves of bloom. The mix of upland and lowland species, sited according to the topography, will provide diversity for the health and habitat potential of the garden while heightening the aesthetic experience.
The Aquatic Shelf will create incident and variety at the lake edge while reinforcing the line of the pond wall; drifts of aquatic plants will filter runoff and lake water, reduce algae growth, and attract a variety of songbird and butterfly species.
Large and healthy existing specimen trees will be moved to new locations in the lower topographical zones of the site, where they will cast welcome shade for visitors. The Upland Woodland, composed of tree species suited to well-draining sites, will enclose the site and insulate the garden from the traffic of Constitution Avenue; existing trees suited to this environment will be moved to these zones. Signature Trees will heighten the island’s special character: Visitors will enter the island across the bridge through a row of willows extending over a shelf of water lilies; a major planting of magnolia varieties will surround the 56 Signers Memorial.