Protea susannae, in Afrikaans the stinkblaarsuikerbos (stinking leaf sugar bush), has several unusual features:
It grows in limestone soil of the Bredasdorp to Albertinia coastal region, also known as the Agulhas Plain or strandveld, whereas proteas are commonly found in acid soil.
The leaves have an unpleasant sulphurous smell, especially when crushed or bruised, while proteas are mostly odourless.
The six or seven series of broadly imbricate involucral bracts have some brown colouring on the outer surfaces, especially in the outer rows, blending with the pink. This is present even at the budding stage, as seen in the photo (Rourke, 1980; Coates Palgrave, 2002).