Leptospermum scoparium is emerging as an economically important plant for the commercial production of mānuka honey and essential oils, both exhibiting unique antibacterial attributes. To support its domestication this is the first quantitative genetic study of variation for L. scoparium traits. It utilised plants from 200 open-pollinated families derived from 40 native populations, from across the species range in Tasmania, grown in a common garden field trial. The traits studied were survival, growth, and the flowering traits precocity, the timing of seasonal peak flowering, flowering duration, and flowering intensity. Significant genetic variation was evident at the population level for all traits studied and at the family level for three traits—growth, flowering precocity, and time to peak flowering. These three traits had moderate to high narrow-sense heritability estimates ranging from 0.27 to 0.69. For six of the traits studied, population differences were associated with climate attributes at the locations where seed was collected, suggesting adaptation to the local climate may have contributed to the observed population differentiation. Population level geographical trends suggest that genotypes to focus on for domestication originate from the eastern half of Tasmania for precociousness and the western half of Tasmania for earlier time to peak flowering and extended flowering duration.

The commercial value of Leptospermum honey increases relative to the nonperoxide bioactivity provided by the methylglyoxal concentration in the honey, which has been shown to correlate with dihydroxyacetone (DHA) concentration in the nectar from which the honey is derived. We detail a new, reliable method to simultaneously detect and quantify DHA, glucose, fructose, and sucrose levels in Leptospermum scoparium nectar using normal phase liquid chromatography–tandem mass spectrometry. Through use of an internal standard (ribose), and a 10-fold dilution of the nectar solution, repeatable calibration curves were achieved (R 2 > 0.99). Precision was acceptable (<6%) for all analytes of interest and limits of detection ranged from 0.02 mg·L–1 (sucrose) to 1.43 mg·L–1 (glucose). The method was also effective at a 5-fold dilution and across analyte concentration ranges found naturally in L. scoparium nectar. Minimal sample preparation is required and a short analysis time of 6 min per sample is achieved, providing the Leptospermum honey industry with cost-effective and fast sample analysis.