So the lesson I learned here was to emboss my image and then watercolor. I'm just using watercolor pencils and a Blender Pen, but for some reason, I was smearing my inked image. Finally, this version seemed to work.
The bummer is that I took its picture too late in the evening and my flash wasn't cooperating. And the punchline? The card fell off my second-story deck and hit the lawn below, where the sprinkler was on. Now *THAT'S* watercolor!