Organic vegetable rain garden?

Would a rain garden for vegetables be a good idea? Having to install runoff basin for a new home and my husband mentioned making it a rain garden for my vegetables, but I'm concerned about the run off from the yard and roof would have stuff in it that I don't want watering my veggies, not to mention the liner material being somewhat toxic as well. Thanks for any input. Terri

A very interesting idea. I'm no expert but the nature of the rain garden would mean that it might go dry periodically? I'm not aware of any veg plants that would grow in a boggy area which is what you might get if using a liner. I wouldn't use a liner but instead make a depression in the ground to temporarily hold the excess run-off until it drains away and that would provide a deep watering effect. I think you'd have to consider any herbicides that might be used on your lawn that could wash into your vegetable plot. Some permaculture practices use swales - dips in the ground - for growing certain types of plants. You might check that out. You could also use rain barrels to capture rain off of your roof to supplement water during drier times. Good luck!

We don't get enough rain here for me to have any personal experience with rain gardens, but I think part of the point of a rain garden is too clean the water BEFORE it gets to the water system. I think in theory your water is supposed to pass through your non-edible bog plants before going into the area you want to use it. And you want to avoid flushing silt and trash into a pond, whatever you are going to use it for.
I know with rain barrels, you can get a first flush system on your downspout where the first and nastiest water off the roof goes somewhere else. You could also do it as an engineered underground system - basically a leach field for rain water instead of sewage. It would turn into an underground pond with a bog on top in wet weather.
Potentially any severe rain could exceed the capacity of any catchment system - have an overflow and a plan for where it goes after that.
Or as my father used to say "It is hard to remember it floods during a drought, or remember droughts during a flood. But you need to plan for both."

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