Lemon Myrtle

Lemon myrtle is an evergreen tree native to the subtropical rainforests of Queensland, Australia. In its natural habitat it can reach 20 meters, but in cultivation it is typically kept to 3 to 5 meters through regular pruning. The tree produces glossy, lance-shaped leaves with an extraordinary lemon fragrance due to its exceptionally high citral content, the highest of any known plant.

Plant in a sheltered position with full sun to light shade in well-drained, slightly acidic soil enriched with organic matter. In frost-prone areas (below zone 9), grow in large containers that can be moved to a bright, frost-free location during winter. Container-grown specimens typically reach 1.5 to 2 meters and respond well to pruning to maintain a compact, bushy shape.

Water regularly during the growing season, keeping soil consistently moist but never waterlogged. Reduce watering in winter but do not allow the root ball to dry out completely. Lemon myrtle benefits from regular feeding with a fertilizer formulated for acid-loving plants from spring through autumn. Protect from cold winds and frost, which can damage or kill the foliage. Established trees tolerate brief periods to about minus 2 degrees Celsius but sustained cold below freezing is fatal.

Lemon myrtle (Backhousia citriodora) is an evergreen tree native to the subtropical rainforests of southeastern Queensland, Australia. Its natural range extends along the coastal hinterland from around Mackay in the north to just south of Brisbane, where it grows as an understorey or mid-canopy tree in warm, humid rainforest environments. For thousands of years before European settlement, Aboriginal Australians recognised the remarkable aromatic properties of lemon myrtle leaves, using them as a flavouring for food, a fragrant addition to ceremonial practices, and a soothing herbal remedy. The leaves were crushed to release their intense lemon scent and brewed into therapeutic infusions. European botanists first formally described the species in the 19th century, and it was named Backhousia citriodora by Ferdinand von Mueller in 1853, honouring the English botanist James Backhouse who had explored the Australian flora extensively. Despite this early scientific recognition, lemon myrtle remained relatively unknown outside Australia for over a century. It was not until the 1990s that a growing interest in Australian native bush foods sparked a commercial revolution around lemon myrtle. Researchers at universities and government agencies analysed the leaf oil and discovered that it contained the highest concentration of citral of any known plant, far surpassing lemongrass, lemon verbena, and actual lemons. This discovery propelled lemon myrtle into the global spotlight as a uniquely potent natural lemon flavouring and fragrance ingredient. Plantations were established across subtropical and tropical Queensland and northern New South Wales, transforming what had been a wild rainforest tree into a cultivated crop. Today, lemon myrtle is used in teas, seasonings, sauces, confectionery, essential oils, skincare products, and cleaning supplies. It has become one of the flagship species of the Australian native food industry and is now grown commercially in suitable climates around the world, from South Africa to southern Europe and parts of the Americas.

Lemon myrtle prefers well-drained, slightly acidic soil with a pH of 5.5 to 6.5, enriched with compost or well-rotted organic matter. In heavy clay soils, plant on a raised mound or in a raised bed to ensure adequate drainage. Feed every 4 to 6 weeks during the growing season with a fertilizer formulated for acid-loving plants such as azalea or camellia food. Avoid fertilizers high in phosphorus, as Australian native plants are sensitive to excess phosphorus. A layer of organic mulch around the base helps maintain soil moisture and acidity.

Harvest lemon myrtle leaves year-round from established plants by snipping individual leaves or small branch tips. The leaves can be used fresh or dried. For the strongest lemon flavor, harvest mid-morning after dew has evaporated when essential oil content is at its peak. Younger leaves tend to have a more delicate flavor, while mature leaves are more intensely aromatic. Regular harvesting and light pruning encourages bushy, compact growth and a continuous supply of fresh leaves. Avoid removing more than one-quarter of the canopy at once.

Dry lemon myrtle leaves on screens in a warm, well-ventilated area away from direct sunlight for 5 to 7 days, or use a dehydrator set to 95 degrees Fahrenheit. The dried leaves retain their intense lemon aroma for over a year when stored in airtight glass jars away from light. Fresh leaves can be frozen whole in sealed bags for up to 6 months. Ground dried leaves into a powder for use as a versatile lemon seasoning that keeps for up to 18 months stored in a cool, dark place. The essential oil can be extracted through steam distillation for concentrated use.

Lemon myrtle is a versatile culinary herb with a clean, intense lemon flavor. Use fresh or dried leaves to brew a refreshing caffeine-free tea with a pure citrus taste. Add dried ground leaves to shortbread, cheesecake, ice cream, and baked goods as a lemon flavoring. Use whole fresh leaves in fish en papillote, marinades, and cream sauces. Lemon myrtle pairs beautifully with seafood, poultry, and tropical fruits. It is increasingly used by professional chefs as a superior alternative to lemon zest.