Corymbia citriodora Lemon Bush - Lemon-scented gum

The Eucalyptus citriodora, now renamed Corymbia citriodora, is famous for the earthy scent of its foliage from which lemon-scented Eucalyptus essential oil is extracted. It is a hardy tree only in the orange zone, capable of reaching large dimensions in open ground and in favorable climates. Its evergreen foliage with a slightly grayish color emits a fragrance in humid weather. This eucalyptus is also appreciated for its decorative bark, straight trunk, and translucent foliage that provides light shade. While successful germination requires some experience and skill, its cultivation presents no particular difficulty in well-drained soil, even if it is poor and dry in summer. It adapts well to container cultivation, where it can be maintained for several years. This allows amateur gardeners who enjoy exotic plants to protect it from the cold in winter.

The Corymbia citriodora is a tree from the Myrtaceae family native to Eastern Australia, specifically Queensland. In its natural habitat, it can reach a height of about 50m (164ft). On the French Riviera, it rarely exceeds 27m (89ft) in height and 18m (59ft) in width. Cultivating it in containers allows for much smaller proportions, at least during its young years, and outdoor cultivation during the warm season in all regions. It prefers acidic or basic soil (rich in volcanic rocks such as basalt or peridotite), but not too calcareous, with good drainage and low nutrient content. This eucalyptus does not tolerate heavy and compact soils, especially clayey ones. Young plants must be protected from frost.

The lemon-scented Eucalyptus has a sparsely branched habit, with a very straight trunk and a light, underdeveloped canopy. It is covered with fibrous bark that changes colour throughout the seasons: from white to pink or light beige, while flaking into small irregular patches, usually at the end of June. The branches bear evergreen leaves in winter. They are entire, narrow, and lanceolate (ending in a point), measuring 7 to 15 cm (3 to 6in) long and 0.7 to 1.50 m (2 to 5ft) wide. Their colour is a beautiful soft grey-green. The shape of the leaves varies depending on the age of the branch that bears them: on young branches, they are wide, without petioles, pubescent, and slightly wavy. Later, the developing leaves are carried by a long petiole. They elongate and become thinner while becoming leathery and glabrous. In pots, the shrub can be pruned every spring:

Mature trees will bloom in summer. The flowers, cream-yellow in colour, are grouped in inflorescences of 11 to 20 units that arise from the axils of the leaves. The fruits of Corymbia citriodora are small woody capsules containing numerous very fine seeds.

Eucalyptus citriodora can be planted in open ground on a narrow strip of the Mediterranean coast, or in pots anywhere else. It can be used as a specimen tree, in rows, or in groups in a large garden. Traditionally, mimosas (Acacia sp) are among the few shrubs and trees that appreciate the close company of Eucalyptus, which deplete the soil's water and nutrient reserves. In an exotic setting, they can be combined with tall palms (Jubea chilensis), Banksia, Metrosideros, large Grevillea, etc.

Aromatherapy uses: rubbing the foliage on the skin is said to repel mosquitoes. Due to its composition, rich in anti-inflammatory properties, lemon-scented Eucalyptus is traditionally used to relieve rheumatic pain. The essential oil is also known for its calming and relaxing effects in case of stress or difficulty falling asleep.