What is a rain garden?
- A rain garden is a plan pond - a garden bed that you plant with special deep-rooted species. These plants help the water rapidly seep into the soil and away from your house. the rainwater is directed from the downspouts to the
garden via a swale (a stone channel) or plastic piping. The garden captures the water and drains it into the soil within a day.
How to build a rain garden?
- Build swales to channel runoff from the gutters and higher parts of the yard. The water is then absorbed into the soil through the networks of deep plant roots.
- Build a berm in a low spot in the yard. Minimum slope of 1 inch (2 percent) for water to flow into your rain garden.
- Grow a mix of plants adapted to your area and to the different water depths.
What benefits does a rain garden provide?
- Reduces the amount of lawn chemicals and pet wastes that may otherwise run off into local lakes and rivers.
- Absorbs 20%, on average, more rainwater than conventional lawns.
- Reduces drainage problems.
- Replenishes groundwater resources.
- Protected structures and landscaping.
- Can cut down on the amount of pollution reaching creeks and streams by up to 30%.
- Provides wildlife habitat.
- Enhances the beauty of yards.
- Reduces wet or damp basements, the need for sump pumps and the prevalence of muddy puddles in your after a heavy rainfall.
How big should the rain garden be?
- Calculate the rough area of the roof that drains down the spout.
- A 2.400 sq.-ft. rectangular home with a downspout at each corner would have approximately 600 sq. ft. of runoff going to each downspout.
- Multiply by rainfall depth (1 in.) to get the volume of water - 50 cu. ft. in this case.
- If your soil porosity can handle a 6-inches deep garden bed, dividing by 1/2 ft. gives you a 100-sq. ft. (10 x 10 ft.) garden size.
What to plant?
- On the higher edges of the garden bed, position plants that thrive in "average to dry" water conditions.
- In the deepest parts of your garden, choose plants that have "average to moist" water requirements.
- Moisture-loving plants will not thrive in your garden because it is designed to drain all water in 24 hours.
Creeklife: www.creeklife.com | Sources: The Family Handy Man - Rain Garden How to Build; http://en.wikipedia.org/Rain_garden; http://www.aacounty.org/DPW/Highways/Resources/Ringarden/Rain_Gardens_MD_Coastal_Plain.pdf;