Nice one JP. harold summed up my feelings too. Works great as a B&W. Only thing I would add is that I would have preferred no to see the right cactus arm clipped at the edge but it is minor.
This certainly works well as a b&w and your conversion is quite nice. I try to avoid having major elements intersecting in my compositions. Here, the FG cactus intersects on the left side with another cactus. Moving the camera a bit to the left may have lessened or eliminated that intersection. Minor point, as this is really a very nice image and one to be proud of!