You may want to try a Muriatic Acid based cleaner, and if that doesn't remove your stain, then you will need to pressure wash or grind the stone. A last resort would be to replace the stone.
don't know by: David
Dear Jana,
I'm not sure what that bush is, but flagstone is porous, so if something gets in there it will be hard to clean without sandblasting it.
You should call Prosoco at 1-800-255-4255 and ask them if they have a chemical solution. They're the cleaning guys we call for specific info like yours.
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