Flower:

Dense, hemipheric clusters of about 30 flowers whorled around the upper leaf axils and the tip of the stem, typically with only a few blossoms open in a cluster at a time. Flowers are about ½ inch long, tubular, the upper lip notched into 2 parts, the lower lip 3-lobed with the center lobe largest and somewhat ruffled or notched. A line of short hairs between the lower lobes extend inside the tube; the outer surfaces are sparsely short-hairy. 4 stamens barely extend out of the tube. Flower color ranges from rose pink to lavender to nearly white. The calyx is green to purple, densely hairy and nearly as long as the floral tube with awl-shaped lobes.

Leaves and stems:

Leaves are 1 to 2½ inches long and 1 inch wide, egg-shaped, rounded at the base, blunt at the tip, toothless to shallowly toothed around the edges, finely hairy on both surfaces, and short-stalked. Attachment is opposite, with pairs at right angles to those above and below it. Leaves are faintly aromatic when crushed. Stems are square, ascending to erect, unbranched or few-branched, and densely hairy. Plants can form colonies from short rhizomes.

Fruit:

The calyx persists, forming a capsule-like container for the tiny, round, brown nutlets.

Notes:

Formerly known as Satureja vulgaris, Wild Basil reaches the western edge of its range in Minnesota; plants found to our west and in some southern parts of its range are generally considered introduced in those areas. It bears similarities to other members of the mint family, in particular the native Wild Mint (Mentha arvensis) and the aggressively weedy Brittlestem Hemp-nettle (Galeopsis tetrahit), both of which have leaves that are more consistently serrated. Wild Mint has much smaller flowers, only 1/8 inch, clusters along most of the stem, and narrowly elliptic leaves. Brittlestem Hemp-nettle has only 2 to 6 flowers in a whorl, leaves that are longer stalked all along the stem, and is more heavily branched.