Rain gardens are becoming increasingly popular as more and more people are taking responsibility for their “ecological footprint.” A rain garden is a sunken garden that is planted with deep-rooted, water loving plants and grasses in a well-draining basin. Its purpose is to receive runoff from impervious surfaces such as roofs, sidewalks, and driveways. Storm water is redirected into a highly pervious garden. Here it naturally percolates into the groundwater supply while recharging water reserves. Rain gardens can be more than functional; they can also be beautiful and beneficial to wildlife.
Benefits of Rain Gardens
Frequently Asked Questions about Rain Gardens
1. What are the components of a rain garden?
Each rain garden is unique to its particular site, but most will contain some common components such as: a sunken ponding area that is at least 6 inches below the surrounding grade; a highly porous soil medium composed of sandy to sandy loam soil supplemented with compost; a mulch layer; and an assortment of plants that tolerate both wet and dry soils.
Q. Why are rain gardens important?
A. A rain garden improves local water quality by controlling the flow of storm water. It allows storm water to filter through soil and into aquifers rather than “running off” into storm drains and picking up pollutants along the way that will contaminate our rivers, lakes and ocean.
Q. Does a rain garden form a pond?
A. No. The design of a rain garden is intended to allow water to pond for a few hours to two days maximum; depending on the amount of storm water taken into the garden.
Q. Is a rain garden a breeding ground for mosquitoes?
A. No. Mosquitoes need at least 5 days of standing water to lay and hatch eggs, and the standing water in a rain garden will not be around long enough to become problematic. Rain gardens will attract dragonflies and other wildlife that eat mosquitoes.
Q. Do rain gardens require a lot of maintenance?
A. No, rain gardens are low maintenance, especially if planted with native plants that can tolerate a range of conditions. During the first two years, weeding and watering may be needed as the plants establish themselves. Raking fallen leaves is suggested in autumn to allow for easier infiltration of water in the springtime.