Manuka honey is produced by introduced European honey bees feeding on the manuka or tea tree (Leptospermum scoparium) which grows uncultivated throughout New Zealand. Manuka honey is markedly thixotropic and has shown the highest viscosity among a range of studied honeys.

This property is due to the presence of a protein or colloid and is its main visually defining character, along with its typical dark cream to dark brown colour. To be labelled New Zealand mānuka honey, at least 70% of its pollen content should come from Leptospermum scoparium.