Adromischus maximus, the largest member of the Adromischus genus, is a robust, perennial succulent reaching heights of about 20 cm. The plant has fibrous roots. Some stem branching occurs, stems being either erect or decumbent.
The distribution of the species lies in the Northern and Western Cape, in southern Namaqualand and southwards to the Gifberg. This Kirstenbosch specimen had a nearly flowered out, many-flowered inflorescence late in April.
The plant grows on semi-arid shale slopes among sparse scrub. This region receives winter rain although not much. Although the plant is rare, the small habitat population is deemed stable early in the twenty first century (Bond and Goldblatt, 1984; iNaturalist; iSpot; JSTOR; http://redlist.sanbi.org).