Rain Garden Basics

A rain garden is a shallow depression filled with a special soil mix and plants, designed to collect and filter water that flows off hard surfaces, like roofs and driveways. It features three distinct moisture zones:

  • Zone 1 – Flat bottom, planted with sedges, rushes, grasses and other water-loving plants.
  • Zone 2 – Slopes, planted with ground covers or plants that can tolerate occasional standing water.
  • Zone 3 – Outside perimeter; planted with drought tolerant ornamental plants and shrubs.

In a typical installation, a pipe will bring water from one or more downspouts to the rain garden. An overflow pipe or rocky swale will let excess water leave the rain garden during heavy rainfall. The rain garden soil mix and plants work together to quickly infiltrate runoff and remove pollutants. Because of this, rain gardens do not provide the conditions needed for mosquitos to hatch.