It’s raining, it’s pouring –make a rain garden!

How to turn runoff water into a beautiful landscape

rain garden. gardening, eco-friendly gardening, Hudson Valley gardening

I was introduced to the rain garden concept three years ago. As a master gardener volunteer with Cornell Cooperative Extension in Ulster County, I was able to take a training class through a joint project with the Water Resource Department at Rutgers University. This grant-based program not only provided classroom training but also included a budget to install three rain gardens in Ulster County.


The classroom training was excellent, but nothing could compare to helping to design and build the first rain garden, for the Saugerties Senior Citizens Center in my home town of Saugerties. Unlike your garden variety garden, which often features raised beds, rain gardens are landscaped shallow depressions. They are eco-friendy, using native plant species and no fertilizers or pesticides.

In fact, rain gardens help remove these pollutants from the groundwater. Hidden from our eyes, but present nevertheless, are fertilizers, pesticides, and petrochemicals that are washed away during a rainstorm. These pollutants find their way into our ground water, streams, and rivers. The water captured by a rain garden slowly seeps into the ground filtering out these pollutants. In the process the plants will take up the nutrients while the microorganisms in the soil will break down the pesticides. A rain garden can also help mitigate landscape problems such as erosion or water pooling on impervious surfaces. These were some of the challenges to be addressed at the senior center.


Soil composition is key


When choosing a site it’s important to consider the grade of the land, soil composition, and tree roots. The best sites are sunny, far enough from trees to avoid the roots, and have a slope of less than 11 percent.


With these considerations in mind our plan was to redirect the downspouts from the front of the Senior Citizens Center so that the rainwater would drain into the garden rather than accumulating in the parking area. We knew that the key to a successful rain garden is the soil. The ideal soil composition is 50 to 60 percent sand. Soil with a high clay concentration will not work, and any area where there is standing water because of poor drainage conditions is not appropriate.


Fortunately, when the soil test results came back from the lab, this site proved to be an excellent choice. Its high sand content and fertility meant that amending the soil was not necessary and we could move onto the next step of excavating for the garden basin.


Create a basin


Most residential homes will need a garden that measures about 100 square feet with a depth of about 6 inches–this varies based on the soil analysis. A garden of this size can be hand dug, especially with the help of a few enthusiastic friends. For safety’s sake before you dig, make sure you know where the underground water, sewer, gas or electric lines are located and avoid them.

The senior center is a large multi-use center, and the garden was designed to be 400 square feet, requiring some serious digging and the need for excavation equipment. We had the soil redistributed to create a level basin with a berm around it that would help to keep the rainwater where we wanted it.  With the technical part was out of the way, it was time to focus on my favorite part, designing the garden and choosing the plants.

Don't know what plants to include? Find out here!

Barbara Bravo is a garden coach, master gardener and ceramic artist.  She has 24 years experience gardening in Ulster County,