Can I spray and rinse this directly on white rocks that are around my boxwood and holly bushes since there is no bleach or acid in it?

When applying Wet & Forget you can either thoroughly rinse nearby plants with water before and after applying or cover plants with a tarp to avoid spotting. We don't advise rinsing the product off the rocks, as this will remove the product off the surface before it has a chance to work on the green and black stains here.