Lemon Myrtle: Uses, Benefits, and Growing Tips

Few native plants carry the cultural and practical weight of lemon myrtle. Its sharp, citrus scent has drawn people for thousands of years — from Aboriginal healers to modern chefs and natural-product formulators. This guide sorts the solid science from the marketing buzz, covering how to grow it, use it, and what the research really says about its benefits and limits.

Botanical name: Backhousia citriodora · Native region: Subtropical Queensland, Australia · Typical height: 6–8 m (20–26 ft) · Primary uses: Culinary, medicinal, insect repellent · Harvested part: Leaves (fresh or dried)

Six key facts, one pattern: lemon myrtle’s value rests on a single molecule — citral — but that molecule shows up in concentrations far beyond those of lemongrass.

What is lemon myrtle used for?

Culinary uses: flavour in teas, baked goods, syrups

Lemon myrtle leaves — fresh or dried — pack a citrus punch without the acidity of actual lemon. They turn up in teas, breads, biscuits, cakes, cheeses, chutneys, jams, pastas, and vinegars, according to research published in the journal Molecules by the National Center for Biotechnology Information (NCBI) (Molecules journal via NCBI (peer-reviewed research)). The flavour comes from citral, a compound that can exceed 90% of the essential oil’s composition — giving it a potency that lets cooks use less leaf to achieve a strong lemon note.

Essential oil in aromatherapy and natural cleaning products

Steam-distilled lemon myrtle oil appears in soaps, cosmetics, potpourris, air fresheners, disinfectants, and body care products (Molecules journal via NCBI (peer-reviewed research)). Its antibacterial and antifungal properties make it a viable natural alternative to synthetic cleaning agents, though commercial formulations typically blend it with other oils to standardise efficacy.

Traditional Aboriginal uses as medicine and flavouring

For thousands of years, Aboriginal Australians used lemon myrtle leaves in teas to treat colds and fevers, and crushed leaves were applied topically for wound healing (Sanitarium Health Food Company (Australian health-food brand)). This traditional knowledge — passed down orally — predates and, in some cases, aligns with modern scientific findings.

How big does lemon myrtle grow?

Mature height and spread in natural habitat

In subtropical Queensland rainforests, lemon myrtle reaches 6–8 m tall with a spread of 3–5 m. Under ideal conditions it can hit 10–12 m, though such heights are rare in cultivated gardens (Leafy Heaven (gardening information site)).

Growth rate in home gardens

The tree reportedly grows 0.5–1 m per year, faster in warm, humid climates (Leafy Heaven (gardening information site)). This moderate rate means a garden specimen reaches functional size — enough to harvest leaves — within three to four years.

Can it be pruned to stay smaller?

Yes. Regular pruning can maintain a shrub-like size of 2–3 m, making it suitable for smaller yards and even large containers. The plant responds well to cutting, and heavy pruning encourages bushier growth with more leaf production (Molecules journal via NCBI (peer-reviewed research)).

Where is the best place to plant a lemon myrtle tree?

Sun and soil requirements

Lemon myrtle thrives in full sun to part shade with well‑drained, slightly acidic soil (pH 5.5–6.5). Lime is not recommended; the plant prefers permeable, moderately acidic substrates (Molecules journal via NCBI (peer-reviewed research)).

Climate and frost tolerance

Frost intolerant. Two or more nights below 0 °C are deadly to seedlings (Molecules journal via NCBI (peer-reviewed research)). Ideal climates are subtropical or warm temperate — similar to its native Queensland habitat.

Spacing and companion planting

Space trees 3–4 m apart. They do well planted alongside other Australian natives such as bottlebrush or grevillea, but avoid competition with invasive species. The tree loves water but does not tolerate waterlogged roots (Molecules journal via NCBI (peer-reviewed research)).

How to propagate lemon myrtle (step by step)

1. Step 1: Take 10–15 cm semi‑hardwood cuttings from a healthy tree in late spring.
2. Step 2: Dip the cut end in rooting hormone (IBA 0.3% works well).
3. Step 3: Plant in a mix of 50% sand, 50% peat moss and keep consistently moist but not soggy.
4. Step 4: Cover with a plastic bag or propagator hood to maintain humidity; place in bright indirect light.
5. Step 5: Roots appear in 6–8 weeks. Transplant to a 1‑gallon pot for the first year before moving to the garden.

Propagation by seed is slower and less reliable — cuttings preserve the exact citral profile of the parent plant.

What does lemon myrtle do to the body?

Antimicrobial and antioxidant effects

Laboratory studies show lemon myrtle essential oil inhibits Escherichia coli, Staphylococcus aureus, and several post‑harvest fungal pathogens (Molecules journal via NCBI (peer-reviewed research)). Its antioxidant capacity — measured by DPPH and FRAP assays — is linked to phenolic compounds like gallic acid and quercetin.

Digestive aid and immune support

Lemon myrtle tea is caffeine‑free and traditionally used to soothe digestion. Although human clinical trials are sparse, the combination of anti‑inflammatory and antimicrobial activity suggests genuine benefits for gut health, as the Molecules review notes (Molecules journal via NCBI (peer-reviewed research)).

Safety and potential side effects

Generally safe when used as a food herb or tea. However, essential oil concentrations can cause skin irritation and are toxic if ingested in quantities above 5 mL (~1 teaspoon). The Molecules report stresses that high‑dose daily ingestion of concentrated oil is not established as safe (Molecules journal via NCBI (peer-reviewed research)).

What did Aboriginal people use lemon myrtle for?

Traditional medicinal applications

Aboriginal Australians made a tea from the leaves to treat colds, fevers, and respiratory complaints. Crushed leaves were applied to cuts and skin infections as a natural antimicrobial (Sanitarium Health Food Company (Australian health-food brand)).

Use as food flavouring and bush medicine

Leaves were used to flavour cooking — often added to damper (traditional bread) or infused in water for a citrus‑tasting drink. The knowledge of which plants to use and when was passed down through the generations, forming part of the world’s oldest living cultural system.

Cultural significance and knowledge transfer

“The leaves have been used in our healing ceremonies for generations,” says a Warndu co‑founder, an Indigenous‑led enterprise that sources lemon myrtle ethically. “It’s not just a plant — it’s a connector to country and ancestors.” This oral tradition is now being recognised by Western researchers who cite Aboriginal use as the first recorded application of the species (Sanitarium Health Food Company (Australian health-food brand)).

Does lemon myrtle repel midges?

How effective is it as an insect repellent?

Lemon myrtle oil is a reported natural repellent against biting midges (Culicoides spp.) and mosquitoes. Its efficacy comes from citral and other volatile compounds that disrupt insect olfactory receptors. A study in Molecules notes that the oil’s vapour phase can reduce landing rates by 70–80 % under controlled conditions (Molecules journal via NCBI (peer-reviewed research)).

Comparison with synthetic repellents

DEET‑based repellents remain the gold standard for duration — providing 4–6 hours of protection. Lemon myrtle oil typically delivers 1–2 hours, meaning more frequent re‑application. The exact effective dose for field use is not yet standardised, and comparative efficacy trials are lacking.

How to make lemon myrtle repellent at home

• Mix 10 drops of lemon myrtle essential oil with 30 mL of a carrier oil (e.g., jojoba or fractionated coconut oil).
• Add 5 drops of eucalyptus or lavender oil for synergistic effect.
• Shake well and apply to exposed skin; re‑apply every 90 minutes.

Store in an amber glass bottle away from light. Patch test on a small area first.

The pattern is clear: lemon myrtle’s reputation rests on real chemistry and genuine cultural history, but commercial claims often skip the caveats. For Australian growers, the opportunity lies in certified organic leaf and oil, not wild harvest. For global consumers, tea and culinary use offer a safe, effective way to benefit from the plant’s antimicrobial and antioxidant properties.

For home gardeners in warm climates, the choice is straightforward: plant one tree, prune it regularly, and you will have a steady supply of leaves for tea, cooking, and a DIY midge repellent. In colder regions, a container kept frost‑free can deliver the same rewards — just with a bit more care through winter.