This really is a rose, officially a China. In rose shows, it is eligible for the Genesis Award.
The cluster of green you see are really the sepals. I have been told there are true flowers deep inside the cluster of sepals; I have never seen one.
When I took the test to become an ARS Accredited Rose Judge, one of the questions was “What is the ARS color of the Green Rose?” There is no ARS color “green,” so I answered “no clue.” I think I was given partial credit for that answer.
The official color of the flowers of the Green Rose is “white.” Just some rose trivia.