Aloe cooperi is usually a stemless, tall-growing grass aloe, solitary to heights up to 1,2 m or in small groups formed from off-shoots. The plant is variable across its geographical distribution. The roots are thick and fleshy.
The 16 to 20 leaves are two-ranked or distichous, sometimes spiralling in old plants, or even becoming rosette-like. The long, erect, succulent leaves are soft-textured, variably keeled usually in their lower parts and somewhat V-shaped in cross-section. The outer surfaces of the leaves are heavily, irregularly white-spotted low down, the inner ones lightly spotted to unspotted, but slightly longitudinally lined. The other local grass aloe species do not have keeled leaves and are mostly smaller.
The blade surfaces are smooth, sometimes tubercled. The cartilaginous margins are narrow and white, armed with firm but not hard, white teeth up to 2 mm long. These are found on the lower leaf parts, reducing in size to almost disappearing nearer the tips. The leaves become about 70 cm long and 6 cm wide at the base.
The species distribution is in the northeast of South Africa, from KwaZulu-Natal and Mpumalanga to Limpopo; also in eSwatini, formerly Swaziland. Plants occur as far south as Margate and Port Shepstone and north to the Wolkberg Mountains.
The habitat is moist grassland and dry, rocky places from sea level to 1900 m. The habitat population is deemed of least concern early in the twenty first century.
The variety, A. cooperi var. pulchra, is no longer upheld. It grows along the KwaZulu-Natal north coast, a smaller plant with deeply keeled leaves that are toothed only in their lower parts, and bearing red flowers that appear late.
A. cooperi plants are sometimes eaten, cooked as a vegetable; also used medicinally (Smith, et al, 2017; Craib, 2005; Van Wyk and Smith, 2003; Reynolds, 1974; iNaturalist; http://redlist.sanbi.org).