This shrublet grows 50–100 cm (1.6–3.3 ft) tall. The stalkless leaves are hairy near the tips.[1] They are narrow and oblong in shape.[2]
Funnel-shaped flowers are present between August and October.[1][2] They are blue with hairs on the outside and are borne in cymes.[1] The flower buds are loosely arranged to form a globose unit, spreading slightly as they mature. There at least three flowers per cymule.[2] Each flower is 17–30 mm (0.67–1.18 in) long, with the anterior petal lobes being larger than the rest.[2] The anthers are borne on short filaments and the stamens only rarely protrude past the petals.[2] The staminal scales are ridge-like and do not have lateral lobes.[1] They occur well below the throat of the corolla tube, being inserted about 4.5–5 mm (0.18–0.20 in) above the base.[2]
This species has been confused with Lobostemon marlothii. There are, however a few features that can be used to distinguish between the two. Lobostemon decorus has a longer calyx, fewer flowers per inflorescence, pale blue flowers (compared to deep blue with a pinkish base in L. marlothii) and narrowly oblong leaves (compared to the wider and often more lance-like leaves in L. marlothii).[2]
