In August 2023 I painted several rocks using a line painting tool, then finished them with a clear UV spray coat. One of the rocks I put out in the garden with a collection of other painted rocks. A year and a half later, this is the only rock that looks as good as new. The others’ designs cracked and flaked off since they had layers of paint, sometimes quite thick.

My takeaway for this is that if you make or find a rock completely covered in paint, keep it inside. If you want to be super clever and hide your rock in a place it might take someone years to find, apply the paint sparingly. I think some of my planted painted rocks may have returned to their natural color waiting to be found. Those freeze thaw cycles and UV rays are hard on paint.