Lesser Known Australian Essential Oils (Part 1): Kunzea ambigua

In early March 2026, I participated in a Study Tour organized by the International Federation of Essential Oils and Aroma Trades (IFEAT) in Australia. During this trip, we visited farms, growers of aromatic plants, and distilleries producing essential oils across New South Wales, Victoria, and Tasmania. While some Australian aromatic plants and their essential oils, such as Tea Tree oil and various Eucalyptus oils, are well known and widely utilized, there are lesser-known species worth exploring. Below is a focus on one of these lesser-known aromatic plants.

One notable native Australian aromatic plant is the genus Kunzea, which is indigenous to Australia and New Zealand. The genus comprises approximately 42 species of woody shrubs. A particularly significant species is Kunzea ambigua. It is a small to medium-sized shrub characterized by narrow lanceolate leaves and typically grows in sandy and granitic soils, often in areas where other vegetation might struggle to establish. Kunzea ambigua frequently reestablishes in areas that have been previously cleared.

Kunzea ambigua, photo: Brian Walters

Habitat and Distribution

Kunzea ambigua naturally occurs in coastal and near-coastal regions of New South Wales, Victoria, and Tasmania. Locally, it is referred to as “white kunzea” or “tick bush,” due to its tick-repellent properties. 

Map illustrating the natural distribution of Kunzea ambigua

The essential oils are primarily contained within the leaves and terminal branches of the plant. The optimal harvesting period is late summer to early autumn (February to April), when the chemical composition of the oils is most favourable. Once the shrubs reach full maturity, harvesting can be performed mechanically. It is noteworthy that it takes approximately 36 years for a plant grown from seed to reach full maturity.

Physical Parameters of Kunzea ambigua

Oil Yield and Composition 

The essential oil yield from Kunzea ambigua is relatively low, ranging from 0.20% to 0.30% wt/wt.

The oil’s composition consists of approximately 70% monoterpenes and 25% sesquiterpenes.

Monoterpenes include:
- alpha-pinene (30–50%)
- 1,8-cineole (9–16%)
- alpha-terpineol (0–9%)

High amount of alpha pinene and 1.8 cineole suggest potential respiratory benefits and antimicrobial activity.

Sesquiterpenes include:
- bicyclogermacrene (0.5–15%)
- globulol (up to 15%)
- viridiflorol (up to 18%)
- ledol (average around 1.3%)

The significant sesquiterpene content imparts anti-inflammatory properties to the oil,  which may be useful in reducing muscle and joint inflammation.

Additionally, the essential oil may contain notable quantities of leptospermone and beta-triketones, compounds recognized for their insect-repellent qualities (Park, 2017).

Patents Related to Kunzea Oil 
- J.J.D. Hood holds a patent (WO 98177491998) for the use of Kunzea ambigua oil for therapeutic and insect repellent purposes.  
- R.A. Armstrong has a patent (AU 2004/100152, 2004) for a psoriasis ointment containing Ducane Kunzea oil.

References  
Park, C. G., Jang, M., Shin, E., & Kim, J. (2017). "Myrtaceae plant essential oils and their β-triketone components as insecticides against Drosophila suzukii." Molecules, 22(6) 674:683