Kunzea serotina is a common tree or shrub that has an erect growth pattern that forms a pyramid-like canopy. The shrub has a single trunk arising from the ground. Less commonly, it may have 2 to 3 trunks growing at the same time. The bark of Kanuka is a greyish-white to pinkish white colour. It has cracks which become bigger and crumpled as the bark grows older, forming a secondary layer of bark.
The plant has numerous branches which grow at or close to the base of the trunk. The mature leaf has a dark glossy green or bronze-green colour which are soft to the touch. Flowering is from November to May, with peak flowering in January and February. The flower provides a source of food (nectar) for the native bees, birds, gecko, flies, moths and beetles. Flowers later than K.robusta. Very hardy.
Kunzea serotina is fast-growing, but short-lived, living up to 150 years. A juvenile take about seven years to reach reproductive maturity. By then it will be about 1.5m tall. During its short lifespan, the tree can reach a height of 15m, increasing the trunk to about 60 cm in diameter. Kunzea serotina grows on soils that contain rock fragments and in areas where the soil is prone to flooding, steep slopes, and hard rock.
The Kunzea serotina and other Kunzea species are not grazed by any livestock or browsing animal. This makes them good to plant in areas where livestock is currently grazed but more regeneration needs to occur for a proper revegetation programme. As the Kanuka become established, they provide a canopy for more tender or slow-growing species. For more information on plant communities that would use Kunzea as a base for regeneration, we recommend DOC’s publication Native Plant Communities of the Canterbury Plains.
Endemic to New Zealand, Kunzea serotina is found on the lower portions of the Canterbury plains, whereas K. robusta is on the hills such as the Port Hills and Foothill regions.