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Name: David W.
Status: other
Age: 60s
Location: N/A
Country: N/A
Date: 7/16/2003

When using an ordinary water softening system, utilizing salt pellets, will there be any detrimental effect on plants, i.e., house plants or flower beds if the softened water is used to water them? Also, would using potassium chloride be a better solution?

Yes, water softeners can be a problem.

The following should be helpful:$department/deptdocs.nsf/all/webdoc1377

Anthony Brach, Ph.D

I do not see any reason why softened water should cause a problem, the level of sodium replacing the Mg, Ca, Fe etc. ions should not be too extreme. The plants may even prefer a lower sulfide level if that is a problem. Using KCl instead of NaCl is going to be a lot more expensive. A balanced liquid fertilizer would compensate for any of the deficiencies also. Perhaps your question should be directed to a florist, or Department of Agriculture Extension agent. I am sure studies have done on this question.

Vince Calder

Some new thoughts. It may be desirable to let water stand overnight so that any residual hypochlorite will decompose. Some plants could be adversely affected by that although the soil may decomposed the hypochlorite before it is taken up by the plant. Also pH is an important factor for some plants. Dissolved CO2 usually makes tap water a little on the acid side, but for most plants that would be a short term issue since the soil will buffer small amounts of excess acid or base. Of course for hydroponic gardening (no soil) things have to be controlled more closely.

Vince Calder

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