With few exceptions, these plants are native to Australia. More than 600 different species grow there, ranging from sprawling shrubs (many of them bearing the common name “mallee”) to skyline trees. About 150 species have been grown in areas of California and Arizona that have climates similar to the plants’ native Australian habitats; many more have been grown as solitary representatives in arboretums. Eucalypts are the most widely planted non-native trees in these two Western states—for several hundred miles in parts of California.Eucalyptus parvula
Hardy to 0°F (–18°C); one of the hardiest eucalypts. Upright, spreading tree to 25–40 ft. tall and 15–30 ft. wide, with semiweeping branches. Dark to light blue-green, highly fragrant leaves are narrow and usually under 3 in. long. Smooth, tan to grayish bark. Tolerates poorly drained soils and more shade than most.