It is a tall shrub found growing in shaded valleys and on rainforest edges, it has hairy leaves and single, purple flowers.

The calyx lobes are sharply pointed, 6–10 mm (0.24–0.39 in) long, rusty coloured with soft, star-shaped hairs.

The seed capsule is rounded or indented globular shaped, 5–10 mm (0.20–0.39 in) in diameter and covered with soft, silky or star-shaped hairs.

[3][4] Howittia trilocularis was first formally described in 1855 by Ferdinand von Mueller and the description was published in Definitions of rare or hitherto undescribed Australian plants from the type specimen which was found growing on "bushy declivities around Lake King".

[5][6] The genus was named after Godfrey Howitt, a Melbourne physician, in recognition of his work as an amateur botanist.