The Helichrysum populifolium leaf is heart-shaped, its pair of basal lobes conspicuous and rounded, the tip rounded to pointed. The margins are entire to debatably coarse rather than toothed and variably uneven. These leaves are notably large for the genus, about 13 cm long and 11 cm wide.
The blades are cobwebby above and grey or grey-green, while white-felted below. A few large veins radiate with the midrib from the leaf-base, serving the large basal lobes. Larger veins are slightly prominent on the upper surface. The few lateral veins from the midrib angle forward, branching sparingly and petering out before the margins into inconspicuous net-veining. Some veins are also visible on the lower surfaces.
The petioles are white-felted, becoming 7 cm long (Pooley, 1998; iNaturalist; http://pza.sanbi.org).