Gardening

Eucalyptus deglupta

Rainbow gum, Mindanao gum

Evergreen, tropical eucalyptus

For his recently published book, “Exceptional Trees of Los Angeles,” Donald R. Hodel documented more than 1,000 trees in Los Angeles County. From those, he selected 167 remarkable trees based on such attributes as age, historical and cultural value, aesthetic quality and rarity. Eucalyptus deglupta is one very exceptional tree in Southern California: “There is no other tree like it,” Hodel says.

What is so striking about the Mindanao gum is its bark, which is constantly peeling off and shedding long vertical strips. Revealed are beautiful, wet-looking, almost neon colors: bright orange, lime green, mauve, yellow, blood red.

In addition, Hodel says: “The Mindanao gum is opposite from what other eucalyptuses are all about.” Most eucalyptuses are from dry, arid lands such as Australia. This tree is native to the tropical lands of New Guinea, Mindanao Island. With age, it develops buttresses at the base of the trunk, peculiar to tropical trees.

Its crown is rounded, and the branches are pendulous with dark olive-green leaves. A fast grower, it reaches 50 to 75 feet. In the tropics it can grow 15 feet a year.

On the tender side, it will tolerate several degrees of frost. New growth can freeze but later will resprout.

Hodel recommends growing the tree from seed. He suggests that if a tree in a 15-gallon container and a small seedling are planted at the same time, the seedling will catch up in size to the container-started tree in a year or two. A plant grown from seed also may be hardier to drought.

However, container-planted trees leave fewer holes in a new landscape. If you are buying containers, look for a younger tree. Inspect the base for circling, wrapped-up roots. Eucalyptuses have extensive root systems that don’t like to be constrained. Roots that have grown into a tight ball will continue circling and will not provide substantial anchoring in the tree’s later life.

Plant away from the house and sidewalks. This tree looks quite dramatic planted in groves of 20 to 30 and spaced 8 to 10 feet apart. For smaller areas, it makes a good lawn tree; it likes water.

The Mindanao gum is susceptible to the eucalyptus borer, but a little less so than the eucalyptuses with bark that doesn’t shed. A tree is more of a target if it is stressed by overwatering or underwatering.

Eucalyptus deglupta also falls under the category of rare in Southern California; it has not been available here until recently, and few are planted. You can see one very large one in the Mildred E. Mathias Botanical Garden on the UCLA campus, and several line Tiverton Avenue alongside the UCLA Medical Center. There also are several plantings at the Los Angeles State and County Arboretum in Arcadia.

Your local nursery can order containers from San Marcos Growers, Santa Barbara, or order it yourself from the Arboretum Gift Shop. For seeds, contact Carter Seeds, 475 Mar Vista Drive, Vista, Calif. 92083; telephone (619) 724-5931.

“Exceptional Trees of Los Angeles” is sold for $14.95 by the California Arboretum Foundation, 301 N. Baldwin Ave., Arcadia, Calif. 91007; telephone (818) 447-8207.