I find square format intriguing and challenging, and for a couple of years now I have been making a steady stream of pictures intended to be processed as black-and-white and cropped to a square. These may be found in my Flickr set Being Square; below find the latest addition:
I have a color version of this as well, but I like the black-and-white one better. There were essentially two colors in the scene: yellow for the blossoms and green for the stems and leaves. Rendering the yellow with higher values and the green with lower values was an obvious and effective way to monochromatize (is that a word?) the frame.