Tree leaves that are coated with a silver-to-white, powdery, waxy substance are known as "glaucous." Glaucous-leaved trees come in a range of heights, textures, forms and colours, from small, multitrunked deciduous trees to large, columnar evergreens. They also have a range of cultural requirements, though most tend to thrive in warmer climates. These waxy surfaces help trees remain cool by reflecting direct sun away from the plant, according to the University of California at Los Angeles.
For Partial Shade
Partially shaded sites receive less than four hours a day of direct sunlight or a constant, equal mixture of shade and sun. The Oklahoma redbud (Cercis canadensis ssp. retisus) has waxy, leathery, heart-shaped leaves that turn yellow in autumn. This deciduous tree grows to 30 feet tall with a 20-foot spread and thrives in sun to partial shade and a range of soils. Oklahoma redbuds bloom with a profusion of bright pink flowers in spring and is hardy in U. S. Department of Agriculture hardiness zones 6 to 9.
The shrubby podocarpus (Podocarpus macrophyllus var. maki) has waxy, glossy, dark-green needles that grow in a spiral. This drought-tolerant evergreen grows as a small tree or large shrub in zones 7 to 11 and reaches heights to 35 feet with a 12-foot spread. Shrubby podocarpus trees prefer sun to partial shade and require well-drained soil.
For Moist Sites
Poorly-drained soil presents a challenge, as most trees can't thrive in wet sites. A few waxy-leafed trees tolerate moist to wet soils. The swamp willow (Salix caroliniana) has long, narrow leaves with a waxy, silver-white coating on their lower sides. This native tree grows naturally in swamps and marshes and tolerates salt spray. It blooms with small, white flowers in early spring. Swamp willows prefer partial shade and moist to wet soils. The swamp willow grows to 30 feet with a similar spread.
The southern magnolia (Magnolia grandiflora) has thick, waxy, broadleaved foliage and blooms with large, aromatic white flowers in spring. This evergreen prefers sun to partial shade and well-drained soil, but tolerates very moist sites. Southern magnolias grow to 8 feet tall with a 40-foot spread and are hardy in zones 7 to 9.
For Full Sun
Plant sun-loving trees in sites that receive all day sun exposure. The Chinese hibiscus (Hibiscus rosa-sinensis) grows as a small tree in warmer climates. It has 6-inch long, dark-green, waxy and lustrous leaves. This deciduous tree blooms with showy white, yellow, pink and red flowers. It grows to 8 feet tall and prefers full sun and well-drained soil. Chinese hibiscus trees are hardy in zones 8 to 11.
The live oak (Quercus virginiania) has green, leathery, glaucous leaves. This North American native grows well in full sun and tolerates a range of soils, including compacted and clay sites. It is hardy in zones 7b to 10. This deciduous tree grows to 50 feet tall and spreads to 80 feet.
For Dry Sites
Some trees require regular irrigation to thrive, while others tolerate drought conditions. The white or Colorado fir (Abies concolor) has 2-inch-long, waxy, blue-green needles. This evergreen grows to 50 feet tall with a 30-foot spread and has a pyramidal shape. Lower branches become pendulous with age. White firs are hardy in zones 3 to 7 and prefer sun to light shade and moist, well-drained soil. They tolerate heat and drought.
The buttonwood (Conocarpus erectus) has waxy, evergreen foliage that grows up to 8 inches long. Buttonwood trees reach heights to 45 feet with a 30-foot spread and grow in a symmetrical, vase shape. They have ridged, scaly bark and are hardy in zones 10 to 11. Buttonwoods prefer full sun but tolerate a range of soils, from sand to acidic, and tolerate both wet sites and drought.
- University of Calfornia Los Angeles: Glaucous Leaves of Calathea Lutea
- North Carolina State University Extension; Trees; Erv Evans
- North Carolina State University Extension; Landscaping Small Trees and Plants; October 31, 2008
- North Carolina State University Extension; Salix Caroliniana; Alice B. Russell
- North Carolina State University Extension; Durham Master Gardener Newsletter; Michelle Wallace; November 2010
- Ohio State University: Abies Concolor