Rain Gardens Provide a Sustainable Landscape Feature

John Orick, Purdue Master Gardener State Coordinator, Department of Horticulture and Landscape Architecture, Purdue University

Have you ever wondered how to handle a drainage or erosion prone area in your home landscape? Well, maybe these problem areas could be just the place for a rain garden. A rain garden is a garden designed with a depression to catch stormwater runoff from your landscape, driveway, sidewalk, or house roof. Instead of stormwater runoff flowing across your driveway, sidewalk or other impervious surfaces, bringing potential pollutants with it to the stormwater drain and out to rivers, lakes, or streams, this water stays in the rain garden and soaks into the soil. The garden is placed in the landscape and sized to catch the amount of water from the impervious surfaces flowing into it. For example, a 1,500 square foot home can produce over 5,000 gallons of stormwater runoff from 1 inch of rainfall. Likewise, larger industrial sites such as a shopping center with over 200 square feet of roof and over 350,000 square feet of parking area produces over 285,000 gallons of water runoff! The plants used in a rain garden are selected based on where they will be planted in the garden. Plants that do well in dryer conditions are chosen for the slope and top of the depression. Plants that grow well under temporary flooding (24 hours or less) are selected for the floor of the depression. Both native plants and horticultural cultivars can be used in rain gardens. However, native plants are often recommended due to their deep rooting characteristics. Rain gardens play an important role in stormwater runoff conservation and in the prevention of water pollution.

Related Articles, Publications, and Websites

Purdue Rainscaping Education Program, https://ag.purdue.edu/Extension/rainscaping

The Blue Thumb Guide to Raingardens: Design and Installation for Homeowners in the Upper Midwest, Rusty Schmidt, Dan Shaw, and David Dods, 2007.

Clear Choices for Clean Water, http://www.clearchoicescleanwater.org

Wabash River Enhancement Corporation, http://www.wabashriver.net/

Rain Garden App, University of Connecticut, http://nemo.uconn.edu/tools/app/raingarden.htm

The Southern Lake Michigan Rain Garden Manual, Illinois-Indiana Sea Grant, http://www.iisgcp.org/catalog/l2l/LMrain_garden.php

Rain Gardens Go With the Flow, Rosie Lerner, Purdue Yard and Garden News, November 17, 2011, www.agriculture.purdue.edu/agcomm/newscolumns/archives/YGnews/2011/November/111117YG.html

Purdue Horticulture Building Rain Garden in Action, https://www.youtube.com/watch?v=YrPX0s5H-kY

Click to enlarge picture

Graphic from www.clearchoicescleanwater.org

Rain garden installed outside the Purdue Horticulture Building (photo by John Orick)

Residential rain garden in West Lafayette, IN (photo by Laura Esman)