Whenever i think of rainbows, or rainbow colours, i'm always so linear in that i think of it from left to right. But i like this because it goes from right to left. It's nice to see a different view point. I really like your tree though, i can never make a tree look right. It's beautiful.
The order of colour of a rainbow really depend on which part you are looking at By the way, I was not particularly happy with the depth of the tree, or more specifically, the lack of it I am happy you thought so