Hello Pascal -- I have been looking at this since you posted it, enjoying it and thinking about it -- musing, you know. . . I love the atmosphere, it is indeed lonely, beautiful, a little sad. What I have been thinking about is whether I think the two different tones work, and now, I think I am ready to say that I think they do. The orchid is a bit warmer than the cooler background, and this creates a bit more distance for me. Did you find Minor White" I think one of his most famous photos is "Windowsill Dreaming" I think you'd like it.
All that having been said, it's really as simple as this: wonderful photograph!