The thinly succulent stems of Senecio muirii may creep along the ground or grow erectly. Soft in the new growth, they become woody lower down. Leaves are about spiralling up the stems. Old stems become leafless lower down, retaining notable scars when the leaves drop off.

Yellowish leaf margins, here with few traces of toothing, but prominently displaying the translucent veins, are visible in the picture (Smith and Crouch, 2009).