Answer: Water from a fountain shouldn't be harmful to plants, unless the water contained chlorine. Replacing the affected soil with fresh topsoil should have remedied the situation. You'll need to replace at least the top 12" of soil to keep residual chemicals from being drawn up into the new soil through evaporation. Failing that, you might want to keep your new plants in their nursery pots and sink them into holes in the beds until the soil stablizes.
As for the worms on your roses, a really good botanical to use is Bt (Bacillus thuringensis). This is extremely effective against caterpillars.
Best wishes with your garden!
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