Blue roses don’t occur in nature, at least not real true blue roses. Roses don’t have the pigmentation that can produce blue, though deep reds that tend to violet are not an impossibility. These flowers are most often man-made.
Real or not, blue roses have gained meaning on their own. The idea of roses being blue is quite loved in literature, where they are depicted as symbols of love, prosperity, and immortality. They represent something that is extraordinary, impossible, and unattainable, like a dream that can never be truth and will always remain out of reach because it cannot exist in reality.
Or, if you like, a flight of fancy and a bright imagination.
I’m not particularly fond of roses, but these varieties – blue, purple, lilac, even black – make me smile because they’re not actually real. It might be nice if they were, but then the novelty of it is gone. It’s not unattainable anymore; it’s not extraordinary because it’s real.
And where’s the fun in that?