Scientific: Corymbia citriodora (formerly Eucalyptus citriodora)
Common: lemon-scented gum, blue spotted gum, lemon eucalyptus
Family: Myrtaceae
Origin: Coastal and nearby inland zones of Queensland in northeastern Australia.
Pronounciation: Cor-RIM-bee-a ci-tree-a-DOOR-a
Hardiness zones
Sunset 12-24
USDA 9-11
Landscape Use: This is a striking, vertical accent tree for groupings in large and expansive landscape spaces, trunk accent, commercial oil production.
Form & Character: Strongly upright and narrow becoming more rounded when fully mature, refined, thin, often with a sparse and open canopy as if on a low carb diet.
Growth Habit: Evergreen, woody, broadleaf perennial tree, moderate to fast growth rate to 60- to 80-feet tall in Phoenix, though up to 150-feet tall in southern California and in northeast coastal Australia. Canopy spread usually much lees than height.
Foliage/Texture: Greyish-green lanceolate leaves that taper to an acuminate tip, generally 5-inches long, only slighly falcate, distinct single central vein transects leaf length; medium fine texture.
Flowers & Fruits: Small white summer flowers, inconspicuous, fruit pediculate, brown capsules when mature, inconspicuous.
Seasonal Color: None, but this tree's startling trunk characteristics should always be on display.
Temperature: Cardinal temperature range is 25o to 110oF.
Light: Full sun
Soil: Tolerant
Watering: Moderately drought tolerant in Phoenix (meaning some supplemental irrigation is needed).
Pruning: Elevate the canopy base (raise the crown) as necessary, train extensively when young so as to avoid having to later make large pruning cuts leaving gaping wound scars on this tree's otherwise smooth creamy white trunk.
Propagation: Seed
Disease and Pests: None
Additional comments: Lemon-scented gum is marginally-adapted to the desert summer heat and thus is not the best eucalyt for Phoenix. Afterall, it is a coastal tree. Otherwise, this is a majestic tree that really thrives in coastal and inland valleys of southern and central California, and is invasive in some of the moist tropical parts of the work such as Hawaii. As a commercial landscape tree trunk vandalism can be a problem, especially in high traffic landscapes. The essential oils of the lemon-scented gum foliage mainly consist of citronellal.
The cultivars 'Dwarf', 'Pink Dwarf', and 'Baby Citro'TM are dwarf selections from Australian nurseries that grow less than 25-feet tall.
My recommendation: In Phoenix, lemon-scented gum is a bad choice when compared with the more heat tolerant eucalypts such as Corymbia papuana (ghost gum).
