The approach of warmer weather and the melting of winter’s snow provide a unique opportunity to determine a potential location for a rain garden. Those low areas of the lawn that tend to hold onto the snow and stay wet the longest are ideal places to plant some water-loving native plants. Rain gardens are a low-maintenance and fairly inexpensive way to slow storm water runoff and reduce the amount of pollutants that would otherwise end up in our streams, rivers and lakes.
Observe your property during a rain event (or snow melt) and pay attention to where and what direction water is flowing. You can choose to locate the rain garden either between the source of runoff (usually a roof or pavement) and the runoff destination, or simply plant the runoff destination if it happens to be a low spot that temporarily holds water.
By utilizing areas of your property that are already wet, you can eliminate the need to move a lot of dirt and instead just focus on planting the right plant species that can tolerate wetter conditions. Choose a variety of native flowers, sedges, rushes and grasses to mimic the natural relationships found in the wild. Also take into consideration the height, texture, bloom time, and flower color to keep the garden visually interesting in every season. A diverse plant mix will also serve a variety of pollinator species.
Once the garden is planted, it will require some maintenance, especially during the first two years. During the first growing season, a new rain garden will need watering about twice a week (unless it rains). Weeds should be removed by hand at least monthly. Additional weeding sessions may be needed in the spring and early summer when the growing season is at its peak. Once native plants are established, they will be able to thrive without manual watering and will outcompete and shade out many of the weeds.
At the end of the growing season, leave the dead plant material and seed heads standing. They will provide important food and shelter for wildlife during the winter months. Once new growth reaches 4” to 6” tall in the spring, dead plant material can be cut back and removed.
Be sure to document the establishment and growth of your rain garden for your Wildlife Habitat Council certification. Many WHC wildlife programs record pollinators visiting the rain garden as well as plant growth.
With a just a little bit of effort to install and maintain a rain garden, you can help protect your community from flooding by recharging the local and regional groundwater supply, help protect rivers and lakes from pollutants carried by stormwater runoff, enhance property aesthetics, and provide valuable habitat for birds and pollinator insects.