HELP

I need help right away. I live in Montana so just planted my garden last week. The nightmare started yesterday. I noticed my marigold leaves were turning a silver/white color. I didn't pay much attention because the blossoms looked healthy. Today I found that this silver white has spread to my salvia, snapdragons and even to some of my perennials. I need help desperately to stop this.

I pulled all of the marigolds (at least 3 dozen) and removed leaves from other plants that were showing the same silvey white. It is not powdery mildew because it doesn's rub off. It's a very shinny silver look.

Please, please, can anybody help me?