Veronica anagallis-aquatica is a biennial or short-lived perennial herb from fibrous roots, stems erect, to 1 m long, mostly smooth.
Leaves opposite, stalkless, clasping stem (lower sometimes very short-stalked), elliptic, to 10 cm long, 5 cm wide, margin toothed to smooth, leaves of autumn shoots stalked, more rounded.
Flowers pale blue, to 0.8 cm wide, corolla deeply 4-lobed; inflorescences unbranched, in leaf axils, many-flowered; blooms May-July (Hough 1983).
Fruit a 2-parted capsule to 0.4 cm and about as wide, above old calyx, flattened, scarcely notched at top; fruits July-Sept. (Hough 1983).
Wetland status: OBL.
Frequency in NYC: Very infrequent.
Habitat: Ditches, wet soil.