What is the difference between using chlorinated water on plants compared to deep well water?

Asked February 25, 2017, 8:17 AM EST

For years people have touted the use of well water over tap (chlorinated) water in growing plants and especially organic growing. What this article is essentially saying is that there is no problem with watering your plants with chlorinated water and it is perfectly fine? So why do so many farmers prefer deep well sources over tap? Is it because of the availability of a well in rural areas or is well water cleaner and safer (obviously whether it is well or tap it needs to be tested for pathogens - see Flint, Michigan water contamination) and contain more and better minerals and elements that help the micro organisms thrive? Or in other words "better"? Why go to all the effort and initial expense to have a well drilled at all if there is no difference? Or is it based solely on economic issues?

It has also been stated not to use chlorinated water in making compost tea because it kills the beneficial micro organisms that you are trying to create - it has to be de-chlorinated beforehand.

What about long-term use of chlorinated water, where only the top 1/2 inch is affected? What happens to that "dead soil" over continued use? Do you scrape it off and move on?

Apparently, based on this article, using common logic, you would not be able turn it into the other "good" underneath soil because then you have "contaminated" it with the built-up chlorine that has bound itself to the soil particles that have basically filtered it out?

So, the discussion is not whether chlorinated water is necessarily "bad" for plants but that it is definitely not "good". The farmers that grow peppers quite successfully in Florida because of the high calcium content of the ground water might have some input on this.

Is there a "published report" from a scientific study in comparing well water to tap water on growth rates and overall health of the plants over a long period?

Oconee County Georgia

1 Response

Sorry for the delay in writing. I have been trying to find anything in the literature that can address this question definitively. As you probably already know from web searches its not in the body of knowledge.

I talked with a horticulture professor at UGA and he said that chlorine in municipal water when applied with overhead irrigation volatilizes within seconds and would not cause issues. He said it could possibly be an issue if you were using an ebb and flow sub-irrigation system.

In short, I don't think you are going to find any plant responses to the differences in well v/s municipal water. Most of the research on water quality is on preventing scaling in irrigation systems and pH effects on fungicides, etc.

I hope this helps. Sorry there isn't more to offer.