Shrubs [trees], (30-)69-150(-200) cm. Stems erect (brittle), puberulent to glabrous. Leaves persistent, opposite; petioles 3-10(-15) mm; blades deltate to broadly ovate or somewhat hastate, (2-)3-5(-8) × 2-5 cm, bases truncate to cuneate, margins dentate, apices acute, faces glabrous or nearly so, eglandular. Heads clustered. Peduncles 2-14 mm, minutely puberulent. Involucres 4-6 mm. Phyllaries: apices acute, abaxial faces glabrous or nearly so. Corollas white to slightly pinkish, glabrous. Cypselae hispid. 2n = 34.

Flowering mainly (Sep-)Oct-Nov(-Dec), also Apr-Jul. Bluffs, limestone outcrops and slopes, ledges along streams, often in oak-juniper woodlands; 100-900 m; Tex.; Mexico; West Indies (Cuba).

Ageratina havanensis apparently is the only species of the genus in the flora area with evergreen-persistent leaves.