Flower:

A spike-like cluster at the top of the stem and the ends of branching stems in the upper part of the plant. Flowers are about 1 inch across with 4 paddle-shaped pink to purplish petals alternating with 4 narrow darker sepals that are shorter than the petals, 8 long white stamens with purple to brownish tips, and a white style, longer than the stamens, divided and curled at the tip. Behind the flower is a long slender purplish ovary that resembles the short flower stalk. A cluster blooms from the bottom up, the buds typically angled downward, flowers facing outward, and ripening fruit angled up to nearly erect.

Leaves and stem:

Leaves are 2 to 8 inches long, up to 2 inches wide, mostly toothless, somewhat wavy around the edges, tapering to a pointed tip, with a creamy white midrib and little or no leaf stalk.

Early spring leaves are very narrow with horizontal grooved veins that eventually smooth out. Stems are green or reddish and may be stiffly hairy in the upper plant.

Fruit:

Fruit is a slender upright pod that turns purplish red as the seed ripens. When ripe, the pods split open at the tip end, peeling back like a banana peel, dispersing the small brown seed.

Seed has a tuft of white hair to carry it off in the wind. When the seed is gone the remains of the pods turn brown.

Notes:

Fireweed formerly went by latin name Epilobium angustifolium (still listed by the DNR and Bell Herbarium but no longer by Flora of North America, our definitive reference). There are 2 subspecies in North America: subsp. angustifolium (Epilobium angustifolium var. angustifolium) and subsp. circumvagum (Epilobium angustifolium var. canescens), both of which are found in Minnesota though subsp. curcumvagum is uncommon. Subsp. circumvagum is generally a larger plant and more hairy, its leaves have distinct veination and a short stalk.