Question
QUESTION: I water my garden from the water table using a sandpump well. The water is high in iron (discolouring cement, siding, etc.) Several perennials I have planted recently did not survive (bee balm, gallardia, heather). As well, four different varieties of poppy seeds and one of sunflower seeds did not germinate at all. Established plants, however, continue to grow vigourously. Is the high iron oxide content of the groundwater toxic to the young plants and to seeds? My regular gardening centre does not have an answer. Thank you in advance.

ANSWER: Hi Jacob, It's possible iron is the culprit.  Iron toxicity usually appears as brown edges on mature foliage and new foliage may brown completely and it effects different species differently or not at all. If the well is only used for watering, I'd consider adding a filter to remove some of the iron.  A simple swimming pool sand filter may work just fine.
Disease may also be the problem.  Different types of root rot attack certain plants and not others.  I'd consider sending a soil sample for testing to your local university or to an analytical lab. Tell them the problem and see if it's iron.  Also talk to other local gardeners to see if they are having similar problems.  I'm leaning more towards disease, but it could be the iron.  Jim

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QUESTION: Jim, I'm having to go back to your earlier replies to ask a follow-up question. Otherwise, I get the message "too many follow-ups." This adds to confusion. But as I earlier wrote, the pH from each of four separate areas tested was neutral (7.0). Want to surrender?

Answer
This is perplexing.  You have acid loving plants that prefer a pH of 5-5.5 that are thriving and should not be at 7.  So we must assume they are very appreciative of the iron rich water but it obviously is not lowering your pH.  So I don't think iron is the problem, I think we are back to disease and possibly complicated by the iron on those plants that have shown some ill effects.  My first suspect is some type of Pythium.  I think it would be worth treating the area just as a precaution.  Check with your local garden centers for Agri-Fos by Monterray.  It controls Pythium and Phytophora root rots.  If the problem continues, then we have to blame the iron, but I'd rule out disease first.  Good Luck!  Jim