Coloured pencil on watercolour board

I've started this drawing from a photograph I took last autumn at a National Trust garden. Although I bought some lovely coloured pencils a couple of years ago, I'm yet to really knuckle down and make a serious effort with them. I'm more confident with pen and ink, it's much easier to make an impression, colour confuses me in many ways. Will I win or lose the battle with this one? Time will tell...