Raining it in

It seems that most yards have an area that is wet. Those areas are often considered the problem area of the yard. They are the portion of the yard that most people wish wasn’t there or that it could somehow be improved.  A rain garden may just be the answer for those low-lying areas. For this column, I asked Grace Koehler, the sales manager at Pizzo Native Plant Nursery, to help us understand what a rain garden is and how it can best be incorporated into a yard.

What is a rain garden?

A rain garden provides valuable ecosystem services by collecting storm water run-off by either retaining the water on site or delaying the water from entering the storm water conveyance system or regional waterways.  Rain gardens help cleanse storm water pollutants and can provide habitat for beneficial insects and pollinators. Rain gardens can be any shape or size and are easily integrated into the home landscape.

How would a homeowner determine where or if a rain garden might be appropriate in their yard?

Build rain gardens in areas where rainwater runoff naturally flows and can be easily collected. Avoid placing rain gardens in areas where water currently ponds as standing water is an indication that the soil is slow to absorb water.

A rain garden is always appropriate in our climate. Storm water runoff is overwhelming our streams, rivers, and municipal conveyance systems.  Instead of creating landscapes that shed water we should create systems that hold our valuable rainwater on site and help renew our deep water aquifer systems. We can all play a key role in keeping our rivers, streams and lakes clean.

What is the purpose of a rain garden?

To capture and filter runoff from impervious surfaces such as roofs, parking lots, streets, walkways, driveways and in some instances lawns.

What are some of the benefits of rain gardens? 

• Rain gardens reduce the amount of pollutants that wash into lakes, streams, ponds, and wetlands.
• Help sustain adequate stream flow during dry spells through infiltration and recharge.
• Enhance the beauty of your yard and the neighborhood.
• Help protect communities and reduce the likelihood of down stream flooding and drainage problems.
• Reduce the need for costly municipal storm water treatment structures.

Is there a typical size for a rain garden?

Rain gardens are typically 7 to 20 percent the size of the impervious surface generating the runoff entering the garden.

A typical residential rain garden may range from 100-300 sq ft. The size can be adjusted to fit the amount of water being captured and in situations where large volumes of water need to be managed it may be beneficial to construct several small rain gardens rather than one large one.

What are some plants that would be appropriate to plant in a rain garden?  It depends on the size of the area and each site is different as far as cultural requirements. We help professional landscape designers and contractors to create species lists based on the site but generally deeply rooted, low growing native plants such as sedges and flowering plants that will attract pollinators are used most often and provide the most benefits.

In designing a rain garden, what do you recommend?

A diverse selection of native plant species that can tolerate widely fluctuating soil moisture conditions. Design as you would design any other perennial garden choosing plants that have the same cultural requirements and will create a thriving plant community.

Are mosquitoes attracted to rain gardens?

No that is a myth, most rain gardens are dry.

Many thanks to Grace for sharing her extension knowledge about Rain Gardens with us. Pizzo Native Plant Nursery is a wholesale only nursery specializing in native plants.

Kathleen Carr is the owner of The Growing Scene, Inc., a garden center and landscaping company. She can be reached by calling 815-923-7322 or tgsinc12@msn.com. Have a gardening question? Please contact her. She may address it in an upcoming column.

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