Hermannia rudis is an erect or spreading shrublet reaching heights from 40 cm to 60 cm. The specific name, rudis, is a Latin word meaning wild, untilled or unused, maybe referring to the general habit of the plant. H. rudis is a resprouter, soon showing lush new growth after a fire.
The species grows in the Western Cape from the Cape Peninsula to around Swellendam.
The habitat is dry and sandy, coastal flats and rocky lower slopes. The habitat population is deemed of least concern early in the twenty first century (Burman and Bean, 1985; Bond and Goldblatt, 1984; Andrew, 2017; iNaturalist; http://fernkloof.org.za; http://redlist.sanbi.org).