Lemon Myrtle (Backhousia citriodora): Uses, Benefits & How to Grow It

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Backhousia citriodora · Encyclopedia entry · Native Australian botanical

Educational content only; not medical advice.

Lemon myrtle (Backhousia citriodora) is an evergreen rainforest tree native to subtropical Queensland, prized for its intensely lemon-scented leaves. Crush a leaf and it smells more like lemon than lemon itself: its essential oil is among the richest natural sources of citral known.[1] The leaf is used as a caffeine-free herbal tea, a culinary spice and a flavouring. This entry covers the plant, its chemistry, what scientific research does and does not say, and how to use and grow it.

What is lemon myrtle? The plant

Backhousia citriodora is an evergreen tree of the myrtle family (Myrtaceae), the same family as eucalypts, tea tree and clove. The genus honours the English botanist James Backhouse, and citriodora simply means “lemon-scented”. The species was formally described by Ferdinand von Mueller in the nineteenth century.

In its native rainforest habitat it grows into a medium-sized tree. In cultivation it is usually pruned as a hedge-like shrub to encourage fresh leaf growth for harvest. The leaves are glossy, lance-shaped and arranged in opposite pairs, dotted with tiny oil glands that release the scent when the leaf is bruised. In summer the tree carries clusters of creamy-white, starry flowers with a froth of stamens, followed by small dry fruits.

Myrtle rust and lemon myrtle

Myrtle rust, a fungal disease first detected in Australia in 2010, affects many native Myrtaceae, and this species is among its susceptible hosts. Surveys have documented significant impacts on native myrtle species in natural ecosystems,[10] so growers manage plantations carefully. Infected new growth shows powdery, egg-yolk-yellow spores; home gardeners are encouraged to report suspected outbreaks to their state biosecurity agency.

Lemon myrtle history and Australian bush-food uses

The leaf belongs to the bush-food heritage of Aboriginal peoples of subtropical Queensland. Since the 1990s the tree has been grown commercially in plantations across Queensland and northern New South Wales, and it is now one of the best-known Australian native botanicals, both at home and in export markets.

Early commercial growers found that the trees respond well to regular harvesting. Plantations are kept as low, dense hedges so leaves can be cut mechanically, then dried at low temperatures to protect the citral. Much of the crop is sold as dried leaf for tea and spice, while a share is steam-distilled for its oil. Interest from chefs in native ingredients has also helped bring the flavour into restaurants, cafés and supermarket products across Australia.

Today the dried leaf is used as a tea, a culinary spice, and a flavouring for cordials, sauces, baking and desserts. The distilled essential oil is used, heavily diluted, in soaps, cosmetics and household cleaning products. Because it grows here, Australian lemon myrtle tea is a short-supply-chain alternative to imported citrus herbs such as lemongrass and lemon verbena.

Lemon myrtle chemistry: citral and the essential oil

The defining compound is citral, a mixture of two aldehydes, geranial and neral. Analysis of the leaf oil has found citral typically makes up over 90 percent of it. That is a higher proportion than in lemongrass, which is why the species is described in the literature as an unrivalled source of citral.[1]

Beyond the volatile oil, the leaf contains non-volatile phenolic compounds. In a comparison of commercially grown native Australian herbs, it showed high antioxidant capacity in laboratory assays.[5] Citral is volatile, however. Storage research on native herbs found that the aroma compounds decline over time and that packaging material affects how much is retained.[8] Store the dried leaf in an airtight, opaque container away from heat and light, and buy in quantities you will use within a few months.

Lemon myrtle benefits: what the research says

Interest in the benefits of lemon myrtle tea is growing, so it helps to be precise about the evidence. Nearly all published research has examined the essential oil or concentrated extracts in the laboratory, not the brewed tea or the culinary leaf in people. The findings are promising as science, but they are not evidence that drinking the tea treats or prevents any condition.

Antimicrobial research (laboratory studies)

In test-tube studies, the essential oil and its citral inhibited a range of bacteria and fungi.[2][3] The same research found the concentrated oil was also toxic to human cells in culture, which is why the oil is only used heavily diluted in cosmetic and cleaning products.[3][4]

Antioxidant and anti-inflammatory research (laboratory studies)

Polyphenol-rich fractions from the leaf showed antioxidant capacity[5] and reduced inflammatory markers in cell-culture experiments.[6] In other lab tests they inhibited enzymes studied in relation to metabolic health.[7] These are early-stage findings on isolated extracts.

Human studies

Human research is limited. One small clinical study applied a diluted essential oil to the skin of children with a common viral skin condition.[9] This concerns topical oil, not tea or food, and should not be tried at home.

A note from Pekoe: Lemon myrtle is a food, not a medicine. Information on this page is educational and describes published research; it is not health advice. If you are pregnant, breastfeeding, taking medication or managing a health condition, please check with your GP or midwife before adding herbal teas to your routine.

How to use lemon myrtle

The leaf is versatile. Whole or cut dried leaf suits teas and infusions; finely ground leaf works as a spice in cooking and baking; fresh leaves from a garden tree give a softer, greener flavour. Whichever form you use, start small: the flavour is far stronger than lemon zest. It is easier to add a little more at the end than to rescue a cup or dish that has become too intense, and the aroma is always brightest when the leaf is freshly crushed, ground or brewed just before serving.

How to make lemon myrtle tea

Dried leaf is potent, so a little goes a long way. Oversteeping can bring out a slightly bitter, resinous edge.

1. Warm your teapot or cup with a splash of hot water, then discard.
2. Add about 1 teaspoon of dried, cut leaf per 250 ml cup. Start with less if you are new to it.
3. Pour over freshly boiled water that has rested for a minute (around 90–95 °C).
4. Steep for 3–5 minutes, then strain. Taste at three minutes and adjust next time.
5. Enjoy plain or with a little honey.

How to make lemon myrtle tea from fresh leaves

If you grow the tree at home, fresh leaves make a softer, greener cup.

1. Pick 3–4 young, healthy leaves and rinse them.
2. Tear or bruise the leaves to break the oil glands and release the citral.
3. Pour over 250 ml of just-boiled water and steep for 5–7 minutes.
4. Remove the leaves and serve.

To dry your own leaves, hang small bunches in a warm, dark, airy spot until crisp, then store them in an airtight jar.

Lemon myrtle tea recipe: honey iced tea (Serves 4)

Ingredients

• 4 tsp dried lemon myrtle leaf
• 1 litre boiled water
• 2 tbsp honey, or to taste
• Ice, lemon slices and fresh mint to serve

Method

1. Steep the leaf in the hot water for 5 minutes, then strain.
2. Stir in the honey while the tea is still warm.
3. Cool to room temperature, then chill for at least an hour.
4. Pour over plenty of ice and finish with lemon slices and a sprig of mint.

Cold-brew option: steep the leaf in cold water in the fridge for 8–12 hours instead.

Lemon myrtle tea blends

The leaf lifts many other teas. Try it with green sencha for a bright, grassy cup; with black tea for a lemony breakfast brew; with rooibos for a naturally caffeine-free blend; with ginger for warmth; or with other native botanicals such as anise myrtle and strawberry gum. A good starting ratio is one part lemon myrtle to three or four parts of the base tea.

Cooking with lemon myrtle

Ground leaf is used much like lemon zest or lemongrass, but it is more concentrated, so a pinch to ¼ teaspoon is often enough to flavour a dish for four. Citral is volatile and fades with long, hot cooking, so add the spice towards the end or use it in dishes cooked gently.

• Baking: shortbread, sponge cakes, muffins and cheesecake bases.
• Desserts: infuse into cream, custard or sugar syrup for panna cotta, ice cream or poached fruit.
• Savoury: rub onto fish, chicken or prawns with salt and pepper, or stir into a butter sauce.
• Dressings and drinks: whisk into vinaigrettes, or steep in sugar syrup for cordials and cocktails.

Buying and storing lemon myrtle

Dried leaf is sold in three main forms. Whole leaf keeps its aroma longest and suits slow infusions. Cut leaf, the usual tea grade, brews quickly and blends easily with other teas. Ground leaf is the spice grade used in cooking; because it has the most surface area, it loses its scent fastest.

Look for leaf that is olive green rather than brown, with a strong citrus smell as soon as the pack is opened. A dull or dusty smell is a sign of old stock. Australian-grown leaf is widely available, and buying from a grower or specialist supplier usually means fresher product with a shorter time since harvest.

At home, keep it in an airtight, opaque tin or jar in a cool cupboard, away from the stove, sunlight and strong-smelling spices. Research on native herbs shows that the volatile aroma compounds decline during storage and that the type of packaging makes a measurable difference.[8] For the best flavour, use tea-grade leaf within six to twelve months and ground spice sooner.

Lemon myrtle vs lemongrass vs lemon verbena

All three are used for a lemony, caffeine-free infusion, but they are unrelated plants with different characters.

Of the three, the Australian tree has the highest citral content in its oil,[1] which explains its stronger aroma. Swap it into recipes that call for lemongrass or lemon verbena, but use about half the amount.

How to grow lemon myrtle

The tree is a rewarding garden plant in warm-temperate and subtropical climates, including coastal New South Wales and Queensland, and makes an attractive screen or hedge.

• Position: full sun to part shade, sheltered from strong wind. Young plants are frost-tender, so protect them in cooler areas.
• Soil: well-drained, slightly acidic soil enriched with compost. Avoid heavy clay that stays wet.
• Pots: it grows well in a large container for several years, which suits balconies and cooler climates where it can be moved.
• Water and feeding: water regularly while establishing and during dry spells; feed in spring with a slow-release native fertiliser.
• Pruning and harvest: tip-prune to keep it bushy and encourage the tender new leaves that are best for tea. Leaves can be picked year-round.
• Watch for myrtle rust: check new growth for yellow spores and remove affected shoots.

Lemon myrtle FAQs

What does lemon myrtle taste like?

It tastes like a very concentrated, creamy lemon with hints of lime and lemongrass, without the sourness of lemon juice. Dried leaf is stronger than fresh, and oversteeping or using too much can make it slightly bitter.

Does lemon myrtle tea contain caffeine?

No. The tea is made only from the leaf of an Australian native tree, not from the tea plant Camellia sinensis, so it is naturally caffeine-free. If you blend it with green or black tea, the blend will contain caffeine from those leaves.

Can I use lemon myrtle instead of lemongrass?

Yes. It works well in most recipes that call for lemongrass or lemon zest, including curries, marinades, desserts and drinks. It is much stronger, so start with about half the amount and add more to taste, adding it late in cooking to keep the aroma.

Is lemon myrtle safe to eat?

The leaf has a long history as a bush food and is widely sold in Australia as a culinary herb and tea. Use it in normal food amounts. The concentrated essential oil is different and should not be swallowed or added to food or drinks.

What is lemon myrtle tea good for?

Most people drink lemon myrtle tea for its flavour: a clean, intense lemon taste with no caffeine. That makes it an easy evening cup and a popular alternative to lemongrass or lemon verbena. Laboratory studies have looked at the leaf’s antioxidant and antimicrobial compounds, but these have not been tested as health outcomes in people drinking the tea.

Does lemon myrtle tea have side effects?

Brewed at normal strength, the tea is widely enjoyed as a food and beverage. The concentrated essential oil is different: citral can irritate skin and was toxic to human cells in lab tests at high concentrations,[3] so never add essential oil to tea. Stop drinking it if you notice an allergic reaction, and speak to your GP if you have concerns.

Can I drink lemon myrtle tea during pregnancy?

Please check with your GP or midwife before drinking herbal teas while pregnant.

References

1. Southwell IA, Russell M, Smith RL, Archer DW. Backhousia citriodora F. Muell. (lemon myrtle), an unrivalled source of citral. Journal of Essential Oil Research. 2000;12(6):735–741.
2. Wilkinson JM, Hipwell M, Ryan T, Cavanagh HMA. Bioactivity of Backhousia citriodora: antibacterial and antifungal activity. Journal of Agricultural and Food Chemistry. 2003;51(1):76–81.
3. Hayes AJ, Markovic B. Toxicity of Australian essential oil Backhousia citriodora (lemon myrtle). Part 1. Antimicrobial activity and in vitro cytotoxicity. Food and Chemical Toxicology. 2002;40(4):535–543.
4. Hayes AJ, Markovic B. Toxicity of Australian essential oil Backhousia citriodora (lemon myrtle). Part 2. Absorption and histopathology following application to human skin. Food and Chemical Toxicology. 2003;41(10):1409–1416.
5. Konczak I, Zabaras D, Dunstan M, Aguas P. Antioxidant capacity and phenolic compounds in commercially grown native Australian herbs and spices. Food Chemistry. 2010;122(1):260–266.
6. Guo Y, Sakulnarmrat K, Konczak I. Anti-inflammatory potential of native Australian herbs polyphenols. Toxicology Reports. 2014;1:385–390.
7. Sakulnarmrat K, Konczak I. Composition of native Australian herbs polyphenolic-rich fractions and in vitro inhibitory activities against key enzymes relevant to metabolic syndrome. Food Chemistry. 2012;134(2):1011–1019.
8. Chaliha M, Cusack A, Currie M, Sultanbawa Y, Smyth H. Effect of packaging materials and storage on major volatile compounds in three Australian native herbs. Journal of Agricultural and Food Chemistry. 2013;61(24):5738–5745.
9. Burke BE, Baillie JE, Olson RD. Essential oil of Australian lemon myrtle (Backhousia citriodora) in the treatment of molluscum contagiosum in children. Biomedicine & Pharmacotherapy. 2004;58(4):245–247.
10. Carnegie AJ, Kathuria A, Pegg GS, Entwistle P, Nagel M, Giblin FR. Impact of the invasive rust Puccinia psidii (myrtle rust) on native Myrtaceae in natural ecosystems in Australia. Biological Invasions. 2016;18:127–144.

Educational content only; not medical advice.