Rain gardens offer an attractive alternative to yard puddles
In the last 30 years or so, the population of Delaware’s coastal area has exploded. Much of what used to be wetlands has been paved over, making room for housing developments and condos, or covered by those structures themselves. As the natural landscape is altered further and further from a natural state, rain water must find new ways to reach the water table and drain out to sea and bay.
Coastal Point • Kevin Roberts
Rain garden in South Bethany.
Oftentimes, rain travels along roads and rooftops, collecting pollutants such as oil and heavy metals. And, without proper drainage, these pollutants find their way into the ocean, bays and canals, threatening the ecosystem. Many homeowners also experience flooding problems in their yards, as much of Delaware is close to sea level.
There is a simple and attractive means to deal with both of these problems, however. The addition of a rain garden to a landscape can help filter and drain water both quickly and efficiently. Installing a rain garden is a simple process and, with the help of some of the area’s numerous eco-friendly landscapers, such as Rick Gentile and Chantal Bouchard of Bethany Beach Gardens, the work can be completed in just a few days’ time.
“Rain gardens are an excellent way to turn an un-attractive spot in your yard into a beautiful place,” Bouchard explained. “If you use native plants, they also help attract birds and insects that may otherwise been driven out by development. Once the plants are in the ground, they will build up a good root system, and take care of themselves while helping to re-create a habitat that people may have removed. It really helps the whole ecosystem.”
Bouchard said property owners wanting to put in a rain garden will want to find a location between the source of rainwater, such as a downspout or run off from their house, and its destination. Any low area in a yard where water flows naturally will work well.
“Place your garden in a sunny spot, where puddles occur naturally,” said Bouchard. “The rain garden will filter out pollutants and sediment, which can block sunlight and oxygen from entering water.” According to the Center for the Inland Bays, a rain garden can absorb 30 percent more water than a similarly sized area of lawn.
The first step in the process is to excavate an area 8 to 10 feet wide about 8 inches deep. This is important, because a soil mixture will later fill in this area to allow water to freely percolate through it. The soil mixture for a rain garden should be about half sand content, with 20 to 30 percent of both topsoil and compost added. Gravel can also be added for denser, high clay-content soil. But much of the soil in the coastal area already has a high sand content, making the job that much easier.
The most important decision property owners installing a rain garden will have to make is what kind of plants to add to their new garden. Again, any of the landscapers around town can help chose plants that will be both attractive and suited for a rain garden.
“We carry 80 to 120 types of plants at Bethany Beach Gardens,” noted Gentile, “many of which are unique and almost all of which are native. We don’t sell any invasive species of plants and have a variety of species that are both drought- and water-tolerant.”
Coastal Point • Kevin Roberts
Rain garden in South Bethany.
“Plants such as blueflag or native iris are small but attractive,” added Bouchard. “They’ll bloom purple flowers in the summer and are small enough to work in between other plants. Other great choices for a rain garden are swamp hibiscus, which blooms in late July and August, or carex or lobelia.
“For larger plants, we recommend clethera or wax myrtle, which handles fresh or salt water. Trees such as river birch can be used for larger gardens and can tolerate shade or full sun. If you’re planting a garden that will be aquatic, you want to look for plants such as cattail or pickerel weed.”
Once property owners have an adequate soil mixture and have selected a variety of plants to fill the garden, planting a rain garden is very much like any other gardening. Fill in the excavated area with the mixture of sand/soil/compost, making sure to leave a depression of a few inches, so as not to disturb the collection of water. Property owners may also want to re-direct other puddle areas of their yard to drain into their rain garden. A good rule of thumb is to estimate one small plant per square foot of garden space. Be careful not to over clump the plants, though, as they will certainly grow and fill in the new garden.
Excess soil may be used to create a berm, particularly if the garden rests on a slope. As with most new plantings, a rain garden may require extra attention at first, but once the plants have established themselves, they require minimal water and no fertilizer at all.
“If you’re having trouble with salt content,” Bouchard noted, “you can add a bit of gypsum to your soil.”
When new rain gardeners go to select plants is an ideal time to ask any questions, as there are plenty of landscapers around the area who are more than willing to share their expertise. Bouchard and Gentile, for example, share almost 30 years of combined experience working on both commercial and residential projects.
For additional information on rain gardens, the Center for the Inland Bays recommends the following Web sites:
www.lowimpactdevelopment.org/raingarden_design/whatisaraingarden.htm
www.epa.gov/nps/toolbox/other/cwc_raingardenbrochure.pdf
