A slender and upright shrub to 3 metres tall by up to 3 metres wide.
It has a distribution south from Wollongong in NSW, west to around Bowral and Marulan, extending south to near Braidwood and between Ulladulla and Batemans Bay.
It grows in heath and shrub habitats, as well as, dry sclerophyll woodland and forest on rocky platforms and hills, usually sandstone-derived.
Mature stems exhibit gnarled bark.
Leaves are circular to broad-elliptic (rounded), to 7 mm long and wide, mid-green, arranged in a neat appearance and openly spaced along the branches, with pointed tips and a slightly shiny texture. They are strongly aromatic when crushed.
Leptospermum typically produce solitary flowers, or in small groups of 2s and 3s or more, within the leaf axils. Flowers have 5 petals and sepals and have a symmetrical rotate shape. Stamens are produced in groups of 5 which surround 1 carpel (female part). The prominent feature in Leptospermum is the hypanthium, a cup or vase-shaped receptacle that supports the flower.
In this species, flowers are produced solitarily, to 30 mm in diameter, white through to mauve-pink, occurring between October and November.
The capsules are to 15 mm in diameter and persist after the seed is released.
This is one of the most popular leptospermums to grow and it has been in cultivation for several decades. It is hardy and very useful for cross-breeding to create new hybrids. There are several cultivars available (see below).
It is best grown in in temperate areas where it will flower reliably, although it can grow well in subtropical regions.
The large and dark pink flowers are the big attraction with this species. It requires little pruning and is resistant to frost and salt spray.
It is best grown in a well-drained soil (sandy) in a sunny to part-shade location. It does benefit from supplementary watering in very dry times.
It can be used as a screening plant and a hedge if desired.
Leptospermum are generally susceptible to the webbing caterpillar. Usually, the most effective control method for this pest is removing infestations by hand or, if necessary, you can systematically spray with a suitable pesticide. They are also prone to scale insects which is best treated by spraying white oil solution.
They are easy to propagate from seed or cuttings. Seed available commercially.
There are some cultivars of the species available through the nursery trade. One that the author has found to be attractive in flower ‘Julie Ann’. This is a prostrate form from the Jervis Bay area of New South Wales, growing to a height of 0.3 metres with a spread of up to 1.5 metres. It makes a good groundcover and will flower through Autumn with deep pink flowers.
Another cultivar is ‘Lavender Queen’ with deeper-coloured mauve flowers, growing to a height of 1.5 metres.
Another cultivar is ‘Bobbles’ which is a compact form with white to pink flowers.
Most Leptospermum species are endemic to Australia where most are found in southern areas of the country and many make desirable garden plants. Current estimates recognize about ninety species of Leptospermum along with many cultivars now existing.
The nectar from the flowers of one species (L. scoparium) is harvested by bees, yielding honey, which is marketed as Manuka honey.
The general common name, Teatree, derives from the practice of early Australian settlers who soaked the leaves of several species in boiling water to make a herbal tea.
Many Leptospermum species have an ability to regenerate vegetatively after fire with suckering basal growth and branch-shoots. They will also regenerate by seed.
Leptospermum – derived from the Greek words leptos meaning “fine” or “slender” and sperma which means “seed” referring to the thin brown seeds of the genus.
rotundifolium – from Latin rotundus – meaning round and folius – meaning leaves, referring to the rounded foliage of this species.
It is not considered to be at risk in the wild.
Australian National Botanic Gardens – Leptospermum profile page https://www.anbg.gov.au/leptospermum/
Wikipedia – Leptospermum rotundifolium profile page https://en.wikipedia.org/wiki/Leptospermum_rotundifolium
NSW Flora Online (PlantNET) – Leptospermum rotundifolium profile page https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Leptospermum~rotundifolium
Wrigley, J.W. & Fagg, M.I. (2001). Australian Native Plants – Propagation, cultivation and use in landscaping. 4th edition. New Holland Publishers, Pty. Ltd. Australia.