For generations, the marsh-surrounded town of Shimmer, Maryland has played host to a loose movement of African-American artists, all working in different media, but all utilizing the same haunting color. Landscape paintings, trompe l'oeil quilts, decorated dolls, mixed-media assemblages, and more, all featuring the same peculiar hue, a shifting pigment somewhere between purple and pink, the color of the saltmarsh orchid, a rare and indigenous flower. Graduate...