Answer: That must be persistent stuff! I also wonder if there was some kind of reaction between the two products. Does the label state how long the products remain active in the soil? If not, I suggest you call the manufacturer, or visit their web site. I believe manufacturers are required to list this contact information, so it should be there. If you've discarded the package, you should be able to get info by dialing Ortho (888)-295-0671.
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