There isn't a single color or shape that is native to the photo and just as well. Once I began laying out the basic design, I kept to 2-3 blues and purples. Next, the faint, setting sun had to go in and that's when things really got interesting.
Up to that point, this was a monochromatic winter scene but when the warmer tones of the sun appeared, it prompted the use of pinks, rust and grey-green. Everything began to fall into place from there. It was very tempting to continue to 'polish' it up a bit, but I was very happy with the rougher look and open brushwork.