These rainbow colored trees are real. They're eucalyptus trees that shed their bark showing the colors beneath. The different colors are from the different times the bark shed as the colors underneath change to get back to brown. They start with green, then go to orange and purple, and eventually return to the original bark color where they start the process over and shed again.
The trees are found in warm, humid climates. I wonder if you could grow them here. Let me know what you find out!