Frequently Asked Questions

What is a rain garden?
A rain garden is a strategically located, low-lying plot of earth containing a variety of perennial native plants. After a rainstorm, the garden will accumulate a few inches of water, which will then seep into the ground. This process is preferred over allowing rainwater to run off into streets and storm drains.

What is a Wetland?
Wetlands are a type of ecosystem that is submerged by water for at least part of the year. The Missouri Department of Conservation considers wetlands to be the most productive ecosystem. Wetlands serve as both a habitat, and a breeding place for a number of animals. Some wetland plants metabolize common pollutants such as phosphorus and nitrogen, thus preserving the biodiversity of species living in the body of water by decreasing the likelihood that algae will grow successfully in the water. They can also break down some heavy metals and pesticides. Moreover, wetlands can reduce storm runoff, erosion, and improve water quality.

Why are wetlands disappearing and why is getting rid of them so bad?
In urbanized locations, the amount of water-permeable ground is quickly disappearing as streets are surfaced with nonporous asphalt and more buildings are constructed. Storm water runoff in largely developed locations increases incidences of flooding and carries pollutants directly into nearby creeks, streams, ponds and lakes. Rain gardens are effective in combating the storm water runoff that results from increasing land development.

What does storm water runoff have to do with rain gardens?
As cities industrialize, more and more land is used for buildings and parking lots. Since less water is going back into the ground to be used by plants or trees, or to replenish underground aquifers, the water stays on the surface and eventually runs off into nearby bodies of water. This is one of the major reasons there is so much flooding today, more water is going into bodies of water than they were naturally meant to hold. This wouldn't be such a big problem if we as humans left a flood plain area between development and the bodies of water, but we haven't done that either. Therefore floods are more prevalent and worse than ever before.

What are the benefits of a rain garden?
Essentially a small, self-contained wetland, a rain garden reduces erosion that results from poor water runoff and filters chemical toxins and thermal pollutants from the water. Over time, this natural filtration process will improve the quality of nearby streams and ponds. The native species in the rain garden will attract native wildlife, such as butterflies, hummingbirds, and birds. It will offer shelter to a declining amphibian population, produce food for birds, and support natural mosquito predators. A rain garden will drain water away from your home, reduce yard maintenance, lower water bills by eliminating irrigation and watering requirements, and even improve the property value of your home. You can utilize an undesirable or useless plot of land by transforming it into one of the most aesthetically pleasing component in your yard. Also, there is always the added benefit of restoring natural habitat to Missouri.

What kinds of plants are used in a rain garden?
A rain garden should consist of native plants, preferably perennials. The native species in a rain garden are selected specifically for their high water absorption capacity and their deep-reaching root system that draws water down into the soil. They are extremely hardy plants that are suited for the ranges of soil and climate in Missouri, and they don’t need fertilizers. You can select a wide range of flowers, grasses, shrubs, and bushes. Also, a garden full of natives requires significantly less maintenance than a garden full of non-natives or exotics. For a list of Missouri natives that included in the Team LEAF rain garden, click here.

How much does a rain garden cost?
A rain garden is an extremely cost-efficient method for dealing with the water runoff problems in your yard. Since native species are usually grown locally, they tend to cost less than imported or exotic plants. Also, the cost of purchasing non-native annuals season after season can really add up; a garden full of perennials avoids this issue, since the natives will grow back each year. Finally, watering a regular garden can significantly raise your water bill, especially in the hot months of summer. Since a rain garden demands little water after established, this cost can be eliminated. The cost also depends on whether your rain garden is self-built, or if you hire professional landscapers instead. Already established plants are pricier than a packet of seeds, but they will also expedite the presence of foliage and flowers in your garden. Try a mix of both seeds and plants to find a balance in price and plant growth. For a point of reference, the rain garden that Team LEAF installed was roughly 250 square feet, and it cost about $300 to put in our selves. That works out to $1.20 per square foot, a very reasonable cost.

How much work do I have to put into a rain garden?
As much as you want. The work required for a rain garden is primarily dependent on its size. A very large rain garden will require more work: more digging, more planting and more resources. A small rain garden, however, will consume significantly less energy. You should put some consideration into the design of the rain garden, including soil properties, amount of sunlight, etc. Once your rain garden is established, very little maintenance is necessary.

Will my rain garden attract mosquitoes?
No. Rain gardens are designed to eliminate excess moisture by drawing water down into the ground and away from the surface. If your rain garden is designed correctly, there should be no standing water after two days (at most). Mosquitoes require at least four days to even hatch, and an additional day to develop past the water-dependent pupa stage of life. In fact, rain gardens even attract native insects and animals (such as dragonflies and amphibians) that feed on mosquitoes.

Will a rain garden only work in Missouri?
Absolutely not. Rain gardens will work wherever there is a build up of storm water runoff, be it in New York or in California. The main difference between a rain garden in one part of the country compared to a garden in another location are the plants that make it up. The plants must be native to that region in order to work effectively.


Over 200 Missouri species use wetlands as their primary habitat.

A 180 ft2 rain garden traps 8000+ gallons of water per year.

In the Missouri Bootheel, over 99% of the original swampland is destroyed.

Nearly 70% of the pollution in our streams and lakes comes from stormwater.

Currently, 1.5% (less than 640,000 acres) of Missouri is classified as a wetland.

Before settlement, 10.9% (4.8 million acres) of Missouri's land was classified as a wetland.

Rain gardens can effectively trap and retain up to 99% of common pollutants in urban storm runoff.

Of the 390 bird species recorded in Missouri, 110 species depend on wetlands for part of their life cycle.

A rain garden allows approximately 30% more water to soak into the ground when compared to an area of lawn of similar size.

The primary cause of wetland loss in Missouri and in the United States has been conversion of wetlands to agricultural land.

Information collected from the following sources:
The Terrestrial Natural Communities of Missouri (2005 Edition) by Paul W. Nelson.
Water Resources Report No. 39 (Missouri Wetlands: A Vanishing Resource) by Jane E. Epperson.

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