Rain Gardens

A rain garden is a popular technique of building a garden bed in a low area that accumulates water after a storm. It is planted with native plants that help to collect and filter rainwater and allow it to seep naturally into the ground. By installing a rain garden on your property, you can greatly increase your contribution to preserving clean rainwater, creating natural, native habitats, preventing local flooding and reducing water pollution.

What Is a Rain Garden?

Unlike specific points of pollution, such as some factory discharge pipes, nonpoint source pollution comes from many different spots. From farmlands to suburban lawns, people use the land in ways that cause nonpoint source pollution. And it is also more difficult to control nonpoint sources of pollution.

Why a Rain Garden?

A rain garden is a natural way for you to help solve our stormwater pollution problems, help recharge groundwater, and protect our water resources. A rain garden keeps rain on your property, where it naturally belongs. By creating a rain garden, you can help improve water quality in local streams, rivers, and lakes. You can use rain the way nature intended, instead of throwing this resource away. In addition, rain gardens are attractive landscaping features. They use native species of plants that are adapted to our region, and can be low-maintenance while providing habitat for native wildlife and butterflies.

What Makes a Rain Garden a Rain Garden?

A rain garden resembles a regular perennial garden in many ways. It is designed with deep-rooted plants that come back year after year; it is pretty to look at; it often has lovely flowers, grasses, trees and shrubs.

Differences From Other Perennial Gardens

There are certain qualities that make a rain garden unique.

  • Rain Gardens have a ponding area, but they are not ponds. They often are planted with wetland plants, but they are not wetlands (although you can design a rain garden that mimics a wetland).
  • The garden absorbs and filters rain that would otherwise run off your property and down the storm drain. This stormwater runoff usually comes from an impervious surface that rain cannot soak into, such as a roof or parking lot, or even a lawn.
  • Many of the plants in the garden are native to the region, and have extensive deep roots that help the garden absorb rain. The native plants do not need special attention once they are established.
  • There is a bowl-shaped dip in the garden, which holds the rain while it soaks into the soil.
  • The garden bed is prepared or sometimes replaced to a depth of two feet in order to de-compact the soils and make the garden able to absorb water.
  • A native plant garden that does not have rain directed into it from a hard surface of your property will still be a valuable asset, and will help absorb rain much better than a traditional landscape. But unless stormwater runoff is directed into the garden, it is not a rain garden.

Benefits of Rain Gardens

  • Rain gardens are lovely landscaping features.
  • Rain garden plants create wildlife habitat and attract butterflies, birds, and other wildlife.
  • Rain gardens can save you money. They don't need to be fertilized or sprayed, only weeded and mulched. They reduce the amount of lawn you have to maintain. This makes your yard a healthier place for children and pets.
  • A rain garden on your property makes you part of a solution to stormwater pollution. Rain gardens can potentially absorb hundreds of gallons of rain that would otherwise wash pollution down the street and into the nearest river, stream, or lake. Even small rain gardens can absorb a lot of rain.
  • A rain garden can be part of a stormwater reduction plan to help solve problems of combined sewer overflows (CSOs).
  • Rain gardens can actually remove many of the common pollutants in stormwater.
  • Rain gardens are low maintenance. Once established, they require no fertilizer, watering, or mowing. A once-a-year cleanup, the addition of shredded hardwood mulch to keep the surface moist and tidy, and the removal of weeds and invasive species are all that are required.
  • Rain gardens can contribute to groundwater recharge, a natural process that is interrupted by soil compaction and hard surfaces created during development and building.
  • A rain garden project can educate the public about the problems that stormwater runoff creates, while giving people a beautiful solution.
  • A rain garden project can be part of the educational toolbox used by a community stormwater education team.