Although the Hawaiian Islands are 20 degrees north of the Equator, they are still a tropical climate that never receives a frost. Many plants have originated from this area that are now grown as ornamental in both tropical and subtropical regions.

Many plant species were "discovered" by European plant explorers in this region and were then introduced to the rest of the world. One of these men, David Douglas of Douglas fir fame, lost his life on the islands.

Map of the United States.