Rainbow eucalyptus have a unique multi-hued bark that is its distinctive feature. Patches of outer bark are shed annually at different times, showing a bright green inner bark. This then darkens and matures to give blue, purple, orange and then maroon tones. The previous season’s bark peels off in strips to reveal a brightly colored new bark below. The peeling process results in vertical streaks of red, orange, green, blue, and gray.