Herbaceous perennial 1 to 3 feet tall and wide. Stem is square, characteristic of plants in the mint family. Leaves are heart-shaped and aromatic when crushed. Leaves and stems are covered in downy hairs. Dense spikes of flowers form at ends of stems.
Calyx tube ± 15-veined; calyx 5-lobed; upper 2 stamens longer than lower 2; flower bracts green, withering, generally longer than flowers, often lance-shaped or wider. Stamens not clearly exceeding lower corolla lobes.
Habitat
Oak and pine forest, moist shaded areas, stream banks, roadsides, waste places.
Flower Characteristics
Flowers are 1/2 inch long and have 5 petals united into a 2-lipped tube. The upper lip consists of 2 lobes while the lower lip has 3 lobes and is larger and more spotted than the upper lip. Flowers are white to pale lavender with purple spots.
Leaf and Stem Characteristics
Leaves are opposite, hairy, triangular or heart shaped and have pointed tips. The upper surface is pale green and the lower surface is so densely covered with hairs that it appears whitish. Leaf edges are serrated like the toothed edge of a saw blade.
Fruit and Seed Characteristics
The fruit is brown in color with a smooth surface. Each flower produces a nutlet containing 4 seeds.
Tiny seeds are oval, smooth, and reddish brown with 2 white spots at one end.