This native perennial plant is 1-2½' tall and unbranched. It tends to be short-lived. The central stem is often ridged or angular near the inflorescence. The sessile alternate leaves occur primarily along the lower half of the stem, and are up to 3½" long and 1" across. They are usually lanceolate or narrowly ovate, but are sometimes wider at the tip than the base. Their margins often have widely spaced teeth, but are sometimes smooth. The inflorescence consists of a long spike of flowers about 4-12" in length. The flowers are light blue or white, and about ½" across. Each flower has a smaller upper lip that is divided into 2 lobes, and a larger lower lip that is divided into 3 lobes. There is a purple or dark blue stigma that is strongly exerted from the upper part of the corolla tube, and bends downward at its tip. The base of the flower consists of a tubular calyx with 5 teeth. Sometimes tiny appendages (0-5 mm. in length) occur between the teeth of the calyx. The blooming period occurs during mid-summer and lasts about a month. There is no noticeable floral scent. Later in the year, the flowers are replaced by seedpods. The latter split open at the top, exposing numerous tiny seeds that are easily carried by occasional gusts of wind. The root system consists of a central taproot.