Epilobium coloratum is a perennial herb to 1 m tall (usually shorter), from overwintering rosettes, stem freely branching, often reddish at nodes (Yatskievych 2006).
Leaves opposite, short-stalked, blade lance-shaped, 4-1.5 cm long, 0.5-2.5 cm wide, often reddish, tip long-pointed (acuminate), base usually rounded, margin closely, veins impressed above, shallowly toothed; winter rosette of small, light green, toothed, elliptic leaves.
Flowers pinkish-white, 4-parted, radially symmetrical, petals 0.3-0.5 cm long, 0.2-0.3 cm wide, calyx lobes alternating with petals, stamens 8 pinkish, stigma rounded, white, ovary inferior, elongate, linear; inflorescence much branched, with leafy bracts, reduced upward, flowers numerous, closely spaced; blooms July-Oct.
Fruit becoming dry, linear, 3-6 cm long, 0.1 cm wide, 4-valved; valves curling back to release numerous black seeds 0.2 cm long, each plumed with red-brown hairs; wind-dispersed through fall, into winter.
Wetland status: OBL.
Frequency in NYC: Occasional.
Habitat: Open, wet edges, marshes, swamp forest edges; soil pH 4.5-7.5. Tolerant of partial shade. Intolerant of salt (USDA, NRCS 2006).
Notes: Winter plant with numerous, pale tan, fine, curling pod valves.