When I cut off the end of a green cabbage to make a salad, I noticed the intricate, floral-like design of the piece of cabbage.  I set it aside to try it as a stamp with Green Gold acrylic paint over an intuitive watercolour on paper.  Here is the stamp and a few imprints as an example, not yet meant to be a completed painting.

stamp imprint from cabbage

Cabbage Stamp and imprint in acrylic over watercolour.