Prostanthera rotundifolia R.Br.

Common Name and Growth Form

Prostanthera rotundifolia, commonly known as round-leaved mintbush, is an erect, compact to spreading shrub.

Size Dimensions

It typically reaches 0.5–3 m (1 ft 8 in – 9 ft 10 in) in height and 1.5–2.5 m (4 ft 11 in – 8 ft 2 in) in width.

Branch Characteristics

Its branches are aromatic, covered with short hairs and sessile glands.

Leaf Morphology

The leaves are egg-shaped to roughly round, measuring 3–20 mm (0.12–0.79 in) long and 3–15 mm (0.12–0.59 in) wide, borne on a petiole 2–8 mm (0.079–0.315 in) long.

Inflorescence and Bracteoles

Flowers are arranged in leaf axils near the ends of branchlets, with 1–2 mm (0.039–0.079 in) bracteoles that fall off as the flower develops.

Sepal Structure

Sepals are 4–5 mm (0.16–0.20 in) long, forming a tube 2–3.5 mm (0.079–0.138 in) long with two lobes, the upper lobe being 1.5–2 mm (0.059–0.079 in) long.

Petal Characteristics

Petals are purple to pinkish, 2–8 mm (0.079–0.315 in) long and form a cup-shaped tube.

Flowering Period

Flowering occurs from September to November.

New South Wales and Victoria Distribution

This species is widespread and locally common in woodland, forest, and rainforest margins, often growing in rocky areas in the eastern half of New South Wales and the southern half of Victoria.

Tasmania Distribution and Conservation Status

It also grows in northern and eastern Tasmania, where it is less common and listed as "vulnerable" under the Tasmanian Government Threatened Species Protection Act 1995.

Horticultural Recognition

In horticulture, the species itself and the cultivar 'Rosea' have both earned the Royal Horticultural Society's Award of Garden Merit.