The leaves of Protea susannae is oblong to elliptic with rounded tip and tapering base, curving upwards on the stems. The leaves are finely hairy when young, becoming hairless and leathery later. Leaf margins are entire, thickened and horny. The midrib is prominent and cream-coloured as the margins. Some lateral veining is visible in the picture. The common name, stinkblaarsuikerbos, reveals that these leaves bear a pong, the odour sulphurous.
The leaves are longer than the flowerhead as in the case of the plant in picture, a common but not universal feature (Manning, 2009; Rebelo, 1995; Rourke, 1980; Eliovson, 1967; iNaturalist).