Important Caveat Regarding Rain Barrels
Posted on April 23, 2008 by
Earlier today, I posted about rain barrels, and there were questions about the safety of using the water collected to water vegetables. I looked into a little more, and here’s what I came up with.
A Rain Barrel Project has a collection of quotes from various articles and studies relating to the safety of using rain barrel water on vegetables, and the general consensus is that it’s not a good idea. Materials from the roof wash off with the collected water and can be an issue, depending on the roofing materials used.
The site does have a link to instructions for building a filter that uses sand to make rain barrel water safer to use.
If you’re not up for building a filter, use rain barrel water to wash your car, water your lawn, flowers and shrubs, but avoid use on plants intended for consumption.
I’m considering collecting water in open buckets that I’ll put out when it rains, and cover until needed, but I need to think that through a little more.
[...] UPDATE: Rain barrel water and veggies may not mix — please read this. [...]
that’s good to know! thank you for looking into and sharing
huh…oh right, because it was water from gutters, not just rain. just stick a barrel outside like you said, it is no different than free falling rain on any outdoor plant anyway.
The porblem as I understand it is that modern day roofing tile, asphalt shingles, contain high amounts of zinc. And I guess high amounts of zinc in the water to feed your veggies is bad.
I guess the two things I would worry about with a bucket (after thinking it over a bit) is 1 - mosquitoes (hence the need to cover the bucket after rainfall), and 2 - there was talk in one article about bacteria growth, so I don’t think you want to leave that water sitting for too long, and make sure the bucket is reasonably clean.
Rob– thanks! that’s a very good point!
Rather than rain-barrels we just built up beds with mulch and black earth at each downspout and let the water drain directly into the soil below the beds. We planted deciduous shrubs (lilacs) along the South side and flowering plants. On the North side we planted coniferous to block the winter winds. We never have to water any of these areas- and the shrubs and trees are doing great.