The Rainbow Eucalyptus, Eucalyptus deglupta, captivating observers with its uniquely vibrant and ever-changing bark. This tall, fast-growing evergreen tree, also known as the Mindanao gum or rainbow gum, displays a kaleidoscope of colors across its trunk. Its striking appearance, reminiscent of an artist’s palette.
Native Tropical Habitats
The natural home of the Rainbow Eucalyptus is primarily within the tropical rainforests of the Northern Hemisphere. These trees are indigenous to specific regions in Southeast Asia and the Pacific Islands, including the Philippines, Indonesia, Papua New Guinea, and Timor Leste. In these native environments, they thrive from sea level up to altitudes of approximately 1,800 meters (5,900 feet).
These tropical conditions are ideal for its growth. They require a warm, humid climate with consistent and abundant rainfall, characteristic of rainforest ecosystems. Ample moisture and high humidity are essential, contributing to their impressive height of 60 to 78 meters (197 to 256 feet) in their native habitat. This species is unique among eucalypts as it is the only one with a natural range extending into the Northern Hemisphere.
Global Cultivation and Sightings
Beyond its native range, the Rainbow Eucalyptus is widely cultivated in various tropical and subtropical regions around the world, primarily for its ornamental appeal. These trees are often found in botanical gardens, arboretums, and other public or private collections where the climate is suitable. They require frost-free conditions and consistently warm temperatures, making areas like Hawaii, southern California, Texas, and Florida in the United States prime locations for their growth.
In these cultivated settings, the trees can still reach significant heights, typically around 30 to 38 meters (100 to 125 feet), though this is often about half the height they attain in their natural environments. Examples include the Fairchild Tropical Botanic Garden in Florida, the Huntington Botanical Garden in San Marino, California, and various locations across Maui, Kauai, and Oahu in Hawaii, such as along the Hana Highway and in the Honolulu Zoo. While colors may be less intense outside their native habitat, their striking appearance persists.
The Bark’s Vivid Transformation
The name “Rainbow Eucalyptus” comes from the tree’s distinctive bark, which undergoes a color transformation. As the tree grows, patches of its outer bark shed at different times throughout the year. This peeling reveals a vibrant, bright green inner bark beneath.
Upon exposure to the air, this newly revealed green bark begins to oxidize and age, gradually changing through a spectrum of hues. These colors can include shades of blue, purple, orange, maroon, and brown. The continuous and asynchronous shedding of bark across different parts of the trunk ensures that a variety of colors are visible simultaneously, creating the tree’s characteristic multicolored appearance. No two Rainbow Eucalyptus trees look exactly alike, as their appearance constantly evolves.