Artemisia australis is a clumping, upright (erect), prostrate, or decumbent subshrub or shrub, ranging in height from 0.15 to 0.45 meters, sometimes up to 1 meter tall. The leaves are simple and alternate with ovate blades. The apex is acute or rounded; the margins are deeply lobed or dissected, pinnatifid. The leaves are broadly ovate in outline, measuring 5-7 cm long and 1.5-4.5 cm wide, bipinnate, and deeply lobed. The segments are linear to broadly lanceolate, 1.5-7 mm wide, with obtuse to acute apices. The upper surface of the leaves is sparsely pubescent to glabrous and glandular punctate, while the lower surface is white tomentose. The petioles are 2-2.5 cm long. The flowers are arranged in leafless panicles surrounded by or scarcely surpassing the leaves, approximately 4-7 cm long and 3-4 cm in diameter, forming a pyramidal shape. The branches are widely divergent, with each head 2-3 mm high and 1.5-3 mm wide. The peduncles are usually 8-15 mm long, with slender pedicels 2-2.5 cm long, erect to slightly reflexed. The involucral bracts are narrow to broadly elliptic or obtuse, with margins usually scarious or absent, and the bracts narrow and nearly linear, with a densely canescent lower surface. There are 8-20 florets per head, with the outer ones female and the inner ones perfect, tubular, and 1.2-1.7 mm long, with an outer glabrous surface to densely glandular. The pappus is absent. The fruit is a simple, dry achene (cypsela), brown to straw-colored, compressed or flattened, obconical, viscid, and may be winged or wingless. It typically inhabits exposed windward cliff faces at elevations around 1000 meters.