The Valley

The Valley at Three Oaks Garden (Des Moines, Iowa) is a perched bioswale and damp savanna edge above the Des Moines River floodplain. In principle, it’s an earnest interpretation of the flora of wet ditches.

The primary inspiration for The Valley came from its topography. The backyard here occupies a small, southeasterly aspect of a larger ravine with 9-12% slopes. The street that loops through the immediate neighborhood follows this ravine, making an island of this property and adjoining lots. The view into the floodplain woodland below the garden inspires contemplation on the ecology of the greater landscape and the downward movement of water. 

We gently shaped the existing topography to direct water more intentionally into two catchment basins; one a bund of sorts adjacent to a sitting terrace and the other a longer, elongated basin framed by a row of willows (Salix ‘Hutchison’s Yellow Barked’, a variety used in basketry). This elliptical row of willows was planted in 2019, an early design gesture intended to channel the viewer perpendicular to the water flow across the landscape. As water meanders down the slope, so does the gardener, ambling along a lower axial path until reaching the property boundary and yawing back up the hill. This cuts across the ridge of the bund as it slows the runoff from the side slope of the property and the neighboring lot. Each space unfolds into the next with nuance, a mosaic defined by topography and a moisture gradient from dry to mesic and eventually wet.

We planted 56 species and seeded another 15. We deliberately left some layers less defined, a vacuum for successional activities and regeneration, which we’ll shape with stewardship and intervention in the seasons ahead.