Landscape Architect & Specifier News

JAN 2019

LASN is a photographically oriented, professional journal featuring topics of concern and state-of-the-art projects designed or influenced by registered Landscape Architects.

Issue link:

Contents of this Issue


Page 29 of 117

Researching Soil Types for Rain Gardens by Jim Funai, Assistant Professor of Plant Science and Landscape Technology at Cuyahoga Community College, Cleveland, Ohio 30 Landscape Architect and Specifier News Introduction My research is focused on rain garden planting soils. Namely, the current specification being used across the nation by engineers and landscape architects (most between 60 – 80% sand) is completely useless to a majority of landscape plants. I come from the horticulture side, so of course I simply blamed it on the architects and engineers for not understanding plants at all. The current recommendation, and much of the work done by horticulture minded researchers, was to find plants that could "survive" in this hostile growing environment. Survive? How are we looking for plants that can simply survive? I want to see plants THRIVE. It wasn't until attending a training session at the Interlocking Concrete Pavement Institute, where it all hit me. I sat there, listening to their Director of Engineering, Robert Bowers, describe soil. A phrase he said will stick with me forever. "What's the best way to improve a soil?" Of course, I said it likely needs aeration and a soil test to determine chemical properties and organic material needs…. He smiles, "No, compact it." COMPACT IT? Yes. From his perspective, to build a functioning pavement system and reach the Proctor Density needed by their calculations, soil compaction is vital. From the horticulturist perspective, compaction is likely the biggest challenge we have to growing plants in the urbanized environment. This is when I realized that we need to communicate better between all of our trades in order to provide the beautiful and functional landscapes needed to combat the negative impacts of a growing world population. Below: An aerial view of the test plots in Cleveland, Ohio at the Cuyahoga Community College. Right: Soil Plot 1 with an experimental blend of haydite and compost. Soil Blend Plot 2 containing an experimental blend of 60% Haydite, with 40% in-situ clay loam by volume. Soil Plot 3 includes the Ohio Department of Natural Resources' specified soil for rain gardens with >70% sand content.

Articles in this issue

Archives of this issue

view archives of Landscape Architect & Specifier News - JAN 2019