Diheteropogon amplectens is a perennial grass, 0.3–2 m high, usually glaucous; rhizomatous; basal sheath glabrous, inner often shiny. Leaf blade is 150–300 × to 20 mm, expanded, usually more than 3 mm wide, rarely densely hairy; bases, at least of upper leaves, narrowly to broadly rounded or cordate, clasping stem; young growth waxy. Inflorescence of 2 racemes, racemes 50–100 mm long; internodes and pedicels hairy; internode hollow at apex. Sessile spikelet is 7–9 mm long; lower glume rounded on either side of deep central groove, apex lobed; upper glume acute, mucronate; lemma awn 20–70 mm long, hairy; callus 1–5 mm long, hairy only towards the point; anthers 4–6 mm long. pedicellate spikelet is 9–13 mm; lower glume with or without awn up to 11.5 mm long (variable on same inflorescence), keeled, keels rounded, not winged; upper glume acuminate, awnless. Diheteropogon amplectens flowers during summer, from November to April.