Scientific: Eucalyptus polyanthemos
Common: silver dollar gum, red box
Family: Myrtaceae
Origin: There are three subspecies of silver dollar gum that are found in wooded foothills of southeastern Australia, central and southern tablelands, New South Whales and in central and eastern Victoria, from 400 to 2,500 feet in elevation on stony and gravelly soil on slight slopes.

Pronounciation: Ewe-ka-LIP-tus poly-AN-tha-mos

Hardiness zones
Sunset
5, 6, 8-24
USDA 8 (with cold protection), 9-11

Landscape Use: Large tree for many uses from garden to street tree.

Form & Character: Strongly upright and rugged becoming rounded with age.

Growth Habit: Evergreen woody perennial tree, fast growth to 45 to 75 feet in height with a 30 to 45 feet spread.

Foliage/texture: Juvenile foliage is orbicular, strongly glaucous, sometimes sessile; adult foliage is glaucous to gray green, oval tapering to acuminate tip. Trunk character comprised fibrous brown bark that revolves around the trunk and peels off in flakes and strips, lateral branches are almost smooth throughout and gray; medium texture.

Flowers & fruits: Many clusters of creamy white flowers in winter.

Seasonal color: Glaucous foliage all year creates feeling of space (not the Star Trek or Star Wars kind....). Winter flowers are a subtle accent.

Temperature: Hardy to 14 to 18oF.

Light: Full sun

Soil: Well-drained soil is an absolute must! In Phoenix, leaf chlorosis is common when growing in heavy irrigated soils.

Watering: Infrequent deep summer irrigations.

Pruning: Prune and stake this eucalyptus vigorously when young to achieve an upright habit.

Propagation: Seed

Disease and pests: None

Additional comments: Silver dollar gum is a variable performer in the Phoenix area depending on microclimate and quality of planting stock. Its "hey day" in Phoenix as a landscape tree was in the middle portion of the 20th century. Today, newly planted silver dollar gum trees in Phoenix are few and far between, and mature specimens are generally only seen in the older parts of the city. Juvenile foliage can be used for cut foliage decoration. If you happen to find some young nursery trees for sale, select carefully, prioritizing those with most round bluish color and upright habit. The wood is hard, strong and durable, and has been used for fencing and railways. Like other eucalyptus, it burns hot and long making it a great firewood.