Corymbia citriodora (Lemon-scented Gum) - This is a fast-growing open canopy evergreen tree that has a mainstem that arises from a subterranean lignotuberous base and can reach up over 100 feet tall by 40 feet wide with a smooth uniform powdery white to slightly mottled bark that sheds in late summer into fall and has long narrow yellow-green colored leaves that are lemon scented when crushed. Small white flowers in 3-flowered umbels appear in mid to late winter.
Plant in full sun in a well-drained soil. Requires little to no summer water in coastal California gardens and is hardy to about 24°F. The small white flowers are attractive but not really showy on the plant because the tree is so tall that they are nearly impossible to see, but the beautiful straight trunk is a whitish pink that turns reddish when wet. This tree has long been cultivated in California and is one of the more elegant of the Eucalyptus clan. The strong lemon scent of the leaves is caused by the essential oil citronellal which is distilled for use in perfumes and menthol and in insect repellents.
Lemon-scented Gum is native to temperate and tropical northeastern Australian state of Queensland, where it is found mostly in dry woodlands. This species was long been called Eucalyptus citriodora but the genus Eucalyptus went through a major taxonomic revision in 1995 and botanists then considered the proper name for this plant to be Corymbia citriodora. As a plant that has been a common landscape plant in California for over 100 years, we continued to list it under its older name for many years until general recognition for the name Corymbia citriodora became more accepted. Other commonly cultivated gums that were placed in the genus Corymbia, a genus of about 90 species previously considered to be in a subgenera within the genus Eucalyptus, were the Red-flowering Gum that became Corymbia ficifolia) and the Spotted Gum Corymbia maculata. The merger of Eucalyptus, Angophora and Corymbia is being proposed in Dr. Dean Nicolle's recent article Classification Of The Eucalypts, Genus Eucalyptus but we will continue to list this plant as a species of Corymbia until such time as this change gets recognized so as not to confuse our customers and our own staff. The specific epithet means "lemon-scented". Though most commonly called Lemon-scented Gum, another common name for this tree is Blue Spotted Gum.
Lemon-scented Gum has long been in cultivation in California. According to Harry M. Butterfield in his Dates of Introduction of Trees and Shrubs to California this tree was tree was first introduced into California by R.D. Fox at his Santa Clara Valley Nursery in 1894. Santa Barbara's own Ellwood Cooper planted this species on his ranch in the western Goleta Valley a few years later in 1887 and on tree he planted, now called the Ellwood Queen, has long been listed as the tallest tree of any kind in the Santa Barbara area. In April 2015 this tree was measured at 142 feet in height with a trunk circumference of 165 inches and a crown spread of 95 feet - it is now listed as the National Champion Lemon-scented Gum on the California Big Tree Registry. Other large specimens can be found in the Santa Barbara area such as ones at UCSB, the Santa Barbara main library and at Stow House in Goleta. We have grown this attractive species since the founding our nursery in 1979.
Information about Corymbia citriodora displayed on this page is based on our research about it conducted in our library and gathered from reliable online sources. We include observations made of this plant as it grows in our nursery gardens and in other gardens that we have visited, as well as how the crops have performed in containers in our own nursery field. We will also incorporate comments that we receive from others about this plant when we feel it adds information and particularly welcome hearing from anyone who has any additional cultural recommendations that would aid others in growing it.