A perennial herb with a basal rosette of leaves and 1or more leafless flowering stalks. Flowers in spikes, terminal on scapes (leafless stems), with tiny, white flowers with a 4-parted corolla. The flowering head develops a brownish appearance due to many short bracts subtending each flower. Blooms April–October. Leaves in a basal rosette, lanceolate, with parallel veins and long, tapering petioles (leaf stalks).
This is one of the few "dicot" plants that has leaves with parallel veins. Usually, that characteristic belongs only to the monocots, a large class of plants that includes grasses, lilies, orchids, iris and so on. Dicots, on the other hand, usually have leaf veins that spread out, like those of a maple leaf.
This plantain and the rest of the plantain family are unrelated to the tropical banana-like plantains. Those fruits are in their own family and are more closely related to ginger and cardamom. English plantain has more in common with mints and lilacs.