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Friday - March 08, 2013

From: Washington, MO
Region: Midwest
Topic: Rain Gardens, Trees
Title: Rain garden for Washington MO
Answered by: Barbara Medford


I have a 40' tall bald cypress at the bottom right corner of my sloped yard (slopes from 2 sides, has 3 gutter runoffs directed towards it from 50-70' away). Can I put a series of retaining walls up hill and around tree to act as a rain garden so my lower neighbors don't receive all of my runoff. There is about 8' down slope and 10' to side property lines.


Whoa! We are gardeners, not civil engineers.  We can't even visualize a series of retaining walls up a hill. We would probably be more concerned with the effects of the walls on existing or planned vegetation than anything else. But, since we do not have the perfect answer on the tip of our tongues, here is an article Retaining Wall Design: How to Manage Water

Again, not quite knowing what the situation is, we do most heartily agree with the idea of a rain garden to retain and utilize some of the rainwater. If the Taxodium distichum (Bald cypress) is in the area that will be receiving the runoff, it is a perfect choice. Its roots are nearly impervious to suffocation, and you can see from the first picture below that the roots can very happily stand in water.

Since we really hate not being able to answer your specific question, here are a couple of articles that should be more help than we are:

From Grow Green (Austin TX)  Earthwise Guide to Rain Gardens

From the University of Wisconsin Extension Rain Gardens A How-To Manual for Gardeners


From the Image Gallery

Bald cypress
Taxodium distichum

Bald cypress
Taxodium distichum

Bald cypress
Taxodium distichum

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