New Extension program promotes rain gardens to combat floods, erosion and stormwater runoff
CLEMSON — The Clemson University Cooperative Extension Service and Carolina Clear have launched an initiative to help property owners install rain gardens to mitigate potential flood damage and help protect South Carolina water quality.
The new Carolina Rain Garden Initiative provides property owners a step-by-step, 17-video tutorial called a “Virtual Rain Garden” that provides tips for choosing plants, selecting a location, preparing soil, creating the appropriate shape and depth, selecting mulch and much more. The newly launched website http://www.clemson.edu/raingarden also provides a 16-page informative manual for download, a list of upcoming educational workshops on rain gardens and a map of demonstration rain gardens throughout the state to visit for information.
In addition to providing tips for installing a rain garden, the Carolina Rain Garden Initiative also certifies professional rain garden installers and designers. Certified professionals are listed on the website.
“A lot of people think that a rain garden is a really wet garden, and that’s simply not the case. We can create rain gardens that infiltrate water quickly; that help with stormwater runoff, erosion and flooding issues; and that also function as beautiful landscape features that attract birds, butterflies and other pollinators,” said Kim Counts Morganello, a water resources agent with Clemson Extension’s Carolina Clear program.
Water infiltrates properly designed rain gardens in three days, or often less, so pooling water does not attract mosquitos. A rain garden installed in North Charleston by Extension Master Gardens, for example, was dry less than 24 hours after receiving three inches of rain from Tropical Storm Bonnie, Morganello said. That’s more than 750 gallons of water soaked up in 24 hours by a small 150-square-foot rain garden, she said.
Excessive rainfall can lead to standing water that causes erosion damage and carries a host of pollutants to streams and rivers, including excess fertilizers and pesticides, oil residue, pet waste and other litter. Properly designed rain gardens are landscaped depressions that act as sponges to soak water into the soil where it is effectively filtered by plant roots and microorganisms. Rain barrels can be added to catch and store water that can be used to irrigate the rain garden and other landscape during dry periods.
“One of the reasons we really like rain gardens at Clemson is their ability to reduce stormwater pollution,” Morganello said.
The Extension Service has installed roughly 20 demonstration gardens at public locations throughout Charleston, Dorchester and Berkeley counties to allow residents to view the gardens for ideas. More demonstration gardens will be added throughout the state and will be listed on the Carolina Rain Garden Initiative website.
Karen Piret and her husband, John, recently installed a small 5-by-8-foot rain garden at a rental home they own in Mount Pleasant. Rain was causing erosion around the back porch, washing away landscaping mulch and preventing grass from growing in spots of the backyard, Karen Piret said. The small rain garden was a simple and inexpensive fix, she said.
“There are no more water issues,” said Piret, who graduated from Extension’s Master Gardener program along with her husband. “We are really happy this solved our problems because then we didn’t have to dig a drain and run tubing. That would have been a lot of work.”
George Aaron, also a Master Gardener, installed two rain gardens near his home, one about 10-by-18 feet and a second 6-by-8 feet, to pull water away from his home and rid his yard of puddles after rainfall.
“I live on the marsh, so we also wanted to keep the runoff out of the marsh,” he said. “There was very little cost associated with it.”
Home gardeners interested in installing a rain garden can attend the Rain Garden Workshop for the Home Landscape Nov. 18 in Berkeley County. Professionals interested in learning about rain garden design can attend the Clemson Extension Contractor BMP training Nov. 15 at the Clemson Sandhill Research and Education Center in Columbia. Additional workshops will be scheduled throughout the state in the future. For a list of workshops, visit the Carolina Rain Garden Initiative website at www.clemson.edu/raingarden.