Want a rain garden for nothing or less?

Stop using weed & feed each spring, and simply use fertilizer instead of you want a lush, green lawn. How so?

Well, pull a "lion's tooth" (dandelion) and check out how deep the roots are--a full foot is not uncommon. Then use a spade to take a look at how deep the roots are for your grass--even if you've got thick topsoil, it's probably 3" or less.

Now consider the fact that a big portion of that organic material in your soil is simply the decaying roots of dead annual plants, and it is this organic material that will capture and hold water that would otherwise go elsewhere--the same kind of principle that makes a rain garden work.

In other words, if one simply allows native plants to (within reason) rebuild the topsoil, one will find far fewer problems with runoff. I would tend to apply this concept to farming as well; it may be arguable that the big reductions in topsoil thickness in places like Iowa may be due more to decomposition of the organic material than to actual runoff. On a note I've written about before, maybe it's time to reconsider the practice of corn-feeding livestock. Alfalfa roots are said to be up to 30' deep in the ground.