HAWAI'I GARDENS
Garden's pagoda tree came from Australia

By Heidi Bornhorst

What is that golden-flowered tree by the art exhibit room at "our" Ho'omaluhia Botanical Garden? I think it is so pretty and cheerful with its bright yellow flowers, so sunny even on a lovely cloudy day there on the windward side. — Mr. and Mrs. M.T., 'Aina Haina

Pagoda trees grow in sandy soil in northeastern Australia. They also can be grown in Hawai'i if planted in well-drained soil. Deborah Booker • The Honolulu Advertiser

That great-looking tree, which is usually in bloom, is the pagoda tree. Known to scientists as Deplanchea tetraphylla, it is in the Bignoniaceae or trumpet-flower family.

The clusters of golden flowers are what first draw your eye to this tree. Then you notice the glossy green leaves clustered at the tips of the branches, and the attractive corky bark.

The pagoda tree — named for the shape of the flowers — comes from northeastern Australia, where it grows in sandy and limestone soils. In contrast, Ho'omaluhia is a very wet garden with clay soil. So, Paul Weissich, director emeritus of the garden and designer of the original planting plan for Ho'omaluhia, wisely chose a site on a pu'u, or hill, that is sunny and well drained. This has helped the pagoda trees to thrive.

It's an approach that you can take in a home garden, too. Look for a well-drained, sunny mound, or make a mound, for plants from dry areas that need good drainage.

We received seed for this tree back in 1973 from the Fletcher botanic garden in Australia. This "sister" botanical garden had collected the seeds of the pagoda tree in the wild in Queensland. This is one of the functions of good botanical gardens: We share plant materials and important data about where the plants came from, how well the plants grow (or don't grow; that's important, too), and whether they become pesty or weedy in a new place.

The seeds of this plant are short-lived and must be planted right away. So far it has not turned into a weed, and our staff continues to keep a sharp eye out for any such tendencies.

Many people have asked about this tree and are interested in growing one of their own. Mahalo for enjoying it at "your" garden. Remember: Visiting Ho'omaluhia is free. It is open 9 a.m. to 4 p.m. daily except on Christmas and New Year's Day. Call 233-7323 for information and directions.

Heidi Bornhorst is director of Honolulu's botanical gardens. Reach her at islandlife@honoluluadvertiser.com.