What is a Rain Garden?
A rain garden is a depression designed to temporarily store rainwater runoff from things like roofs, driveways and walkways. During a rainstorm, they catch water, filter it and then allow it to slowly absorb into the ground. This approach improves the quality of the water and takes pressure off of nearby waterways where excess rainwater is directed. Rain gardens use native perennials, grasses and shrubs that love the change from dry to oversaturated conditions.
Designing a Rain Garden
There’s lots of ways to design a rain garden, but I think it’s really important to think about the aesthetic of it form the beginning. In some cases, the rain garden will be a focal point of a yard, and other times it’s less so. In plant selection, you want to make sure you have the right plants for the different zones of a rain garden. What I mean by zones is that some parts will be wet more often and for longer periods of time than others. In places like northern New Jersey, the spring is very wet, so you could see water in the depression 30 to 50% of the weeks from March to June. In other parts of the country, you may see much less such as southern California.
In selected plants, you’ll also want to make sure you get the right heights as well as types. For example, Joe Pye is a super beautiful native plant that does very well in rain gardens, but it gets tall (in some cases 4 to 7ft tall). This means it can block views from inside or obstruct sight lines in your yard. It’s something to consider with the design.
Performance
If you build the rain garden correctly, you can manage nearly all of the rainwater coming off your roof or driveway. This means hundreds, if not thousands, of gallons of runoff will be dealt with in a more natural way. You will be actually doing your part to help the environment. Plus, with the right plants, you will see butterflies, bees and birds visiting your yard.