Eucalyptus Tree

Eucalyptus trees are among the fastest-growing trees available, with some species adding 6 to 10 feet per year under ideal conditions. Choose a site with full sun, good drainage, and ample space, as eucalyptus develops an extensive root system and can reach substantial size within just a few years. Most species prefer well-drained soil with a pH of 5.5 to 7.5 and are remarkably drought-tolerant once established.

Plant container-grown specimens in spring when soil temperatures warm. Avoid root-bound plants, as circling eucalyptus roots rarely correct after planting and lead to instability later. Plant at the same depth as the container and water deeply at planting. Apply 3 to 4 inches of mulch but keep it well away from the trunk. Water weekly for the first growing season, then taper off as roots establish.

Eucalyptus requires minimal pruning for the species that grow as single-trunked trees. Coppicing, or cutting back to near ground level, rejuvenates multi-stemmed species and is practiced commercially for flower-arranging foliage and firewood production. Be aware that eucalyptus wood is notoriously brittle, and mature trees can drop heavy limbs without warning, so avoid placing seating areas, pathways, or structures within the drop zone.

Eucalyptus is a vast genus of flowering trees and shrubs belonging to the myrtle family Myrtaceae, with over 700 recognized species. The genus is overwhelmingly native to Australia, where eucalyptus forests cover approximately 92 million hectares and represent the dominant tree type across most of the continent. A small number of species occur naturally in parts of Indonesia, Papua New Guinea, and the Philippines. Aboriginal Australians have utilized eucalyptus for thousands of years, using the wood for tools, canoes, and shelter construction, and the leaves for traditional medicine to treat wounds, infections, and respiratory ailments. European botanists first formally described eucalyptus in 1788 when the French botanist Charles Louis L'Heritier de Brutelle named Eucalyptus obliqua based on specimens collected during Captain Cook's third voyage. Throughout the 19th century, eucalyptus was introduced to regions around the world including California, southern Europe, South America, and parts of Africa, often for timber production, swamp drainage, and windbreak purposes. In California, massive planting campaigns in the 1850s through early 1900s established eucalyptus groves that persist today, though the trees became controversial due to their fire risk and impact on native ecosystems. Brazil emerged as the world's largest commercial eucalyptus grower in the 20th century, cultivating vast plantations primarily for pulp and paper production. Today eucalyptus is one of the most widely planted hardwood genera globally, valued for its rapid growth, aromatic essential oils, honey production, and ornamental appeal in gardens and landscapes.

Eucalyptus thrives in well-drained soil and tolerates poor, sandy, and gravelly conditions that would challenge most trees. Ideal pH ranges from 5.5 to 7.5. Heavy clay must be amended or mounded for drainage, as eucalyptus is highly susceptible to root rot in waterlogged conditions. Most species require minimal fertilization once established. For young trees, apply a low-phosphorus fertilizer in spring, as eucalyptus is adapted to phosphorus-poor Australian soils and can develop toxicity in phosphorus-rich conditions. Mulch lightly to conserve moisture but avoid deep mulch against the trunk.

Eucalyptus is harvested primarily for its aromatic foliage, which is popular in fresh and dried floral arrangements. Cut branches in the morning when essential oil content is highest. For flower arranging, harvest juvenile round-leaved foliage from coppiced trees, which is more ornamental than the elongated adult leaves. Eucalyptus oil can be extracted by steam distillation of fresh leaves. The wood is valued for firewood, as it burns hot and long, though it should be seasoned for 12 to 18 months before burning.

Fresh eucalyptus branches last 2 to 3 weeks in water and several weeks when preserved with glycerin. To glycerin-preserve, mix one part vegetable glycerin with two parts hot water, stand cut branches in the solution, and leave for 2 to 3 weeks until leaves become supple and slightly darkened. Preserved eucalyptus retains its form and fragrance for months. Air-dried eucalyptus maintains its shape but becomes brittle. Eucalyptus essential oil should be stored in dark glass bottles in a cool location and lasts indefinitely.