Helichrysum marginatum is a creeping, mat-forming dwarf shrublet that grows many branching stems from a woody rootstock. The leafy mat may reach a diameter of 1 m.
The leathery leaves are large compared to the typical size for plants of the genus. The leaves are green, ovate with conspicuously white, hairy margins. Leaf surfaces are glabrous on both sides, i.e. hairless, although young leaves are hairy all over.
The plant grows in the higher elevations (2440 m to 3300 m) of the Drakensberg and the Malutis among rocks and on rock sheets (JSTOR; www.keys.lucidcentral.org).