Leptospermum riparium is a straggly shrub that typically grows to a height of or more and has flaky bark. The leaves are mostly
glabrous, lance-shaped with the narrower end towards the base, usually long, wide, the base tapering to a thin
petiole. The flowers are white, wide and arranged on the ends of leafy side branches. There are reddish-brown
bracts and
bracteoles at the base of the flower buds but that usually fall off before the flower opens. The
floral cup is about long with triangular
sepals about long. The
petals are long and the
stamens about long. Flowering mainly occurs in January and the fruit is a
capsule wide with the remains of the sepals attached and that remains on the plant at maturity. ==Taxonomy and naming==