I have a rather small yard in the Denver area where I have hauled in and arranged about 10-15 tons of rhyolite boulders to form a high border/short retaining wall/rock garden area the full width of my yard. I then filled in behind and between the rocks with "planters mix", a sandy loam with compost mixture. The rocks and soil came from the same supplier. As soon as I started watering plants, the rocks began to effloresce salt! (yes, I've tasted it) Most rocks are covered with a powdery residue. Some have a flaky crusty build up, and some even grow little salty "worms" that stick out from the rock. You can wash it off daily and it comes right back. My rocks are now surrounded by 3-6 inch wide halos of salt-encrusted soil, and so far I have 65 dead plants, mostly near the rocks, but more recently some a good distance away from the rocks. The supplier admitted that there are sometimes salt veins that run through the rhyolite, but says it has never been a problem before, and they still recommend their rhyolite for general landscaping. They suggest that I rinse/flood the rocks frequently to wash and leach the salt away and say that the problem will probably go away.
Now I need advice. I don't know if I need a geologist, a master gardener, or a lawyer, but all of my labor and money has gone for nothing. I have killed unkillable plants and contaminated my whole back yard with this salt, and they want me to "give it time"! Has anyone ever heard of salt contaminated rhyolite? Will this go away, or last for years? Isn't this considered toxic, or at least an environmental hazard? I have yet to approach the supplier with the idea of replacing the rocks, soil, and plants, and providing the labor to do it for me. Does this sound like a legitimate lawsuit? I'd love to hear opinions....HELP!