Kunzea serotina is a tree or shrub that has an erect growth pattern with fastigiate growing branches that form a pyramidal (pyramid-like) canopy.

It has a diameter of 0.2-0.5mm covered with a bud scale, having a yellow-brown to red-brown colour forming an ovate shape.

The midrib supports the upper half with a lengthy cuspidate tip, no lateral veins and oil gland and keel apex ciliate.

Deciduous pherophylls with foliose form and about 0.9–25 mm in length, it has a round end and tapered to at the base.

The flower has a diameter of (2.8-) 5.2 (-8.8) mm with its petals having a white colour flashed with pink and a broadly ovate.

Anther 0.04 – 0.06 x 0.02 x 0.04 mm in length and is the connective gland, orange and flushed with rose in colour when fresh, with the pollen (11.1-) 12.4 (-13.7) μm and the ovary 3-4 (-5) locular.

The Kunzea ericoides complex consists of 10 species that are endemic to New Zealand, seven of which were described for the first time by Peter James de Lange.

[1] North-east of Rangitaiki River K. serotina is abundant where it grows between flat and upland podocarp forest.

K.serotina is distributed throughout South Island, and in the North of Canterbury it is found east of upper Wairau, west of Karamea, and Wangapeka Valley and lakes around Nelson.

[1] The distribution spreads down to East Canterbury along the mountain ranges through upper Hurunui, mainly the Hanmer area and to Sumner.

[6] During its short lifespan the tree or shrub grows to a height of approximately 15m, increasing the trunk to about 60 cm in diameter.

[7] It produces a huge seedbank on the soil surface under the plant, where the seeds await dispersal through rainwater runoff, or germinate if the conditions are viable.

K. serotina colonizes more easily than the native forest or vegetation including pasture land that once dominated the landscape.

[1] Changes in the concentration of nitrogen in the will affect the growth performance of K. serotina; however,[6] limited information is known about the species' soil nutrient requirements.

[9] are not grazed by any livestock or browsing animal, but the flower provides a source of food (nectar) for the native bees, birds, gecko, flies, moths and beetles.