Question
Hi..

I am watering my grass from well water. I know the water has a lot of Iron in it.  Is it harmful to the grass? It seems like the grass may be doing better after I water it with the city supply.  How can I know for sure?

Peter

Answer
You can have a sample of the well water analyzed by the Extension Office in your county or at a reputable laboratory. Explain that you want to find out if there are any harmful agents in it that will hurt the lawn. They will know what to look for and be able to offer you suggestions for remedial action. If they can't, find another Lab. The local Water Authority will give you an analysis of the City water. You can try to compare the two results to decide which item would account for the difference but it is best left to people qualified in the science. Iron can be toxic to grass as the pH number of the soil goes down (more acid). Iron becomes unavailable to the plant as the pH goes higher (less acid or more alkaline). The grass will then show chlorosis.