Hempnettle, common (Galeopsis tatrahit)

Hempnettle, common description

Common hempnettle is a herbaceous annual plant growing to 1 m tall. The plant looks like mint but is taller.

Propagation

Hempnettle is an annual that reproduces by seed.

Similar species

American dragonhead resembles hemp-nettle. As a seedling it can be distinguished by its backward pointing lobes at the base of cotyledon leaves, and by its ovate true leaves with round-toothed edges. As an advanced plant American dragonhead has narrower, elliptic leaves coarsely toothed in an irregular pattern. Seed clusters do not have sharp points like in hemp-nettle.

Distribution

Hempnettle is found throughout Canada.

Identifying Hempnettle, common

Seedling

Cotyledons round to oblong, with a distinct notch at the tip, hairless. True leaves opposite, oval, with coarsely toothed edges, and hairy.

Mature plant

Stems erect, branched, 1 to 3 feet at maturity. Stems square, coarse, swollen below the nodes, with bristly hairs.

Leave opposite, oval, with pointed tips, 2 to 4 inches long. Leaf edges regularly toothed. Bristly hairs cover stalked leaves, especially the upper surface.

Root structure description

Taproot.

Flowers

Purple and/or white, 1/3 to 1 inch long, in dense clusters in the leaf axils. Flowers are 2-lipped, and slightly hairy. Flowers July to September. Seeds develop in the ball-like cluster at the leaf axils. The clusters have sharp points that make the plant difficult to handle. Seeds egg-shaped, grey-brown, with round scar at top, and whitish warts over the surface.