Question: What has caused my hollyhocks to turn tan all over? It’s killing the plants.
Answer: That’s spider mites. Even though they’re nearly microscopic, you can see them if you thump a leaf or two over white paper. Control them with a labeled general-purpose insecticide. For what it’s worth, they often break out toward the productive life of the hollyhocks’ stalks. If the plants have opened most of their buds, you might opt not to treat.