Aloe marlothii plants growing well can be expected to reach a height of around 4 m. When the 50 or so leaves are fully fleshed out and become up to 1,5 m long, the size of these plants can be truly imposing.

The much-branched panicle appearing in winter may be 80 cm tall. It consists of up to 30 horizontal or obliquely angled racemes. Many A. marlothii flowers are orange or yellow-orange.

There is also a much-admired bicoloured form around the Barberton area. Its racemes are halfway pinkish red, the rest cream coloured. Near Utrecht there is a scarlet flowered form (Reynolds, 1974; Coates Palgrave, 2002).