What is a rain garden?
A rain garden is a shallow depression designed to capture and soak up stormwater runoff from your roof or other impervious areas around your home like driveways, walkways and even compacted lawn areas.

Rain gardens protect surface water quality while adding beauty to the yard. Water from the roof or pavement is routed to the garden where it soaks in instead of running off. Native plants with deep root systems help absorb water and filter pollutants.

Typically, rain gardens are supplied with clean water that runs off from rooftops through gutters and downspouts. Water entering rain gardens will slowly seep into the ground, or in large storms, collects for a short time and slowly evaporates. They can be used as a buffer to shoreline areas to capture runoff from the home landscape before it enters a lake, pond or river.

5 reasons to build a rain garden

1. Water that soaks in replenishes groundwater and helps prevent flooding.

2. Rain gardens improve water quality by trapping sediment, fertilizers and other pollutants.

3. They don’t require fertilizer or pesticides and after establishment, don’t need to be watered.

4. Native plants provide food and shelter for butterflies, song birds and other animals.

5. They create an attractive landscaping feature in your yard.

How do I build a rain garden?
Rain gardens don’t have to involve a lot of complicated planning. They don't require much space, can be fitted into oddball shapes and can be readily added to existing buildings. They look nice, and you don't need to be an engineer to build one.

Here are some things to consider when planning your rain garden:

• Put your rain garden in the right place. Examine your yard’s drainage. Place the rain garden down-slope and at least 10 feet away from building foundations and up-slope from stormdrains.
• Size the rain garden correctly. Calculate the square footage of the area where rain will runoff and divide by three. This will give you a rain garden that captures about 30 percent of the water it receives.
• Evaluate existing soils. For heavy clay soils, till in compost to loosen the soil and help plants grow. Compacted soils often cause rain gardens to fail, so keep machinery and vehicles off the area.
• Increase infiltration. Excavate six to eight inches of soil to create a slight depression that catches water. Mound this soil into a berm on the downstream side of the garden.
• Create an attractive design. Rain gardens feature native plants that are attractive and easy to care for. Give your rain garden a tended appearance with neatly defined borders to keep it from looking weedy.

Get more tips on building rain gardens.

Questions?
Contact Mandy Stark, outreach and education specialist.