By Serena Dobson
Rain is probably far from your mind this winter. It’s more likely you’re stressing over snow—the mornings you’ll spend plowing your driveway and the salt you’ll inevitably be tracking into the house. But even though drizzly spring days seem a world away, the winter months are the perfect time to start thinking about planting a rain garden.
Stormwater runoff is a major issue facing the health of waterways all over the world. On impervious surfaces like paved roads, sidewalks, and roofs, rainfall flows unimpeded, collecting pollutants like pesticides and animal waste as well as litter like cigarette butts and plastic. This contaminated water makes its way into storm drains, where it enters our sewer system, or might even flow directly into rivers and stream, where it threatens flora and fauna.
Rain gardens were developed as a way to mitigate this problem. Consisting of vegetation planted within a shallow depression in the ground, they collect, absorb, and filter water that would otherwise run freely through urban areas. Washtenaw County residents are lucky to have a robust rain garden program, run through Washtenaw County Water Resources. The County offers a Master Rain Gardener Course that gives participants the opportunity to gain all the knowledge needed to construct and plant their own rain garden. The prerecorded course and necessary materials are available on their website, along with other helpful resources.
By studying up over the winter and making important decisions about your garden ahead of time—such as location, design, and what plants to use—you’ll feel much more prepared when it comes time to plant. Most sources recommend planting your rain garden at least 15 feet away from any buildings to keep water from pooling around and damaging structural foundations. Utilities like wells and septic tanks will need to be considered, too. As far as location goes, one option is to stake out an area near roof gutters or downspouts but still distant enough from your home that there’s no risk of damage while another is to position the garden further down your yard so that it collects runoff from the lawn as well as from the downspouts. Wherever you place it, your rain garden will need to be downhill from the channel that will be directing the water and situated on flat or slightly sloped ground.
The Master Rain Gardener Handbook suggests making your rain garden be “four to six inches deep and 20–30% the size of the impervious surfaces.” Though you won’t need to start digging until the spring, it’s good to figure out and troubleshoot these measurements ahead of time. Once you know how big your garden should be, you can experiment with different shapes—like a crescent, teardrop, or other organic form—settling on one that complements the existing features of your yard. Don’t be afraid to sketch it out! Putting your ideas on paper is the best way to visualize your garden-to-be.
What native Michigan plants you choose should be dependent on how much sun your garden will be getting. Purple coneflower is perfect for full sun, while wild geranium prefers things to be partly sunny. Plants like fox sedge and black-eyed Susan can thrive in either situation. You might also keep in mind the kinds of pollinators you most want to attract. A garden filled with bee balm and rose mallow would be hummingbird heaven!
Leslie Science & Nature Center (LSNC) will be incorporating a rain garden into the design of their our developing Nature Playscape with their upcoming water play installation in 2023. Using pumps along the perimeter of the water play area, visitors will be able to manipulate a flow of water that will run downhill, feeding a rain garden populated with native flowers, grasses, and shrubs. They will design pumps for ease of use, ensuring that visitors of varying physical abilities can enjoy the feature equally. The rain garden will be staggered down the hill and fed underground by runoff from the water play area. Our water feature will provide an opportunity to educate visitors about informed water usage and the role that rain gardens can play in a healthy urban ecosystem.
By using mindful landscaping techniques like rain gardens, the center can positively contribute to the health and beauty of the local watershed. Rachel Carson wrote in Silent Spring that water must be thought of “in terms of the chains of life it supports.” As you begin to plan your rain garden, consider how this choice will impact all the life around you—your family and neighbors, your pets, the songbirds nesting in your backyard, and the trees in your favorite park. From the smallest insect to the tallest sycamore, we all depend on clean water to thrive, and we as humans have the power to make a beneficial and lasting contribution to our environment.
List of resources:
Rain Gardens: Sustainable Landscaping for a Beautiful Yard and a Healthy World by Lynn M. Steiner and Robert W. Domm
Creating Rain Gardens: Capturing the Rain for Your Own Water-Efficient Garden by Cleo Woelfle-Erskine and Apryl Uncapher
Let’s Build a Rain Garden by Sally Wenczel (children’s book)
Water Resources Washtenaw County: Rain Gardens: washtenaw.org/647/Rain-Gardens
Water Resources Washtenaw County: Master Rain Gardener Class washtenaw.org/675/Master-Rain-Gardener-Class
Huron River Watershed Council: Rain Gardens in Our Watershed: hrwc.org/rain-gardens-in-our-watershed/
Serena Dobson is the Development & Administrative Assistant at the Leslie Science & Nature Center and Ann Arbor Hands-On Museum and holds an MFA in creative writing from the University of Michigan. She loves to hike and birdwatch all over Washtenaw County.
Related Content:
Giwitatigweiasibi. Nottawaseppi. Huron. There are many names for this river birthed in a swamp, meandering south through the center of Ann Arbor and Ypsilanti and onward to Lake Erie. Cos-scut-e-nong, sebee,“burnt oak river,” connecting upstream and down, invites us to a wider sense of self, neighborhood, and community. I spoke with Rebecca Esselman, Executive Director, and Jason Frenzel, Director of Community Engagement, both of the Huron River Watershed Council, about our local river.