Blue sage (Salvia azurea var. grandiflora) of the Mint (Lamiaceae) family is a long lived herbaceous perennial with sky-blue flowers. Other common names include Pitcher blue sage and wild blue salvia. Plants have long, slender and sturdy upright to leaning stems that reach 2 to 5 feet tall. The number of stems increases over the years so that rough, knobby, compact clumps form with a multitude of long, tough and slender, radiating to deeply bedded roots. Early stems have short dense pubescence, but this pubescence may be worn away as the season progresses. Branches, most numerous in the upper portion of plants, grow singly from axils of opposite leaves. Although length of branches varies, in general, lower branches may be 14 inches long with length gradually decreasing toward the plant apex, where lengths may be less than an inch. Long branches may have secondary branches. Plants are drought tolerant; however, leaves wilt during hot dry periods, and flower development is interrupted. Stems and branches are four-sided with broadly rounded corners made prominent by deep central grooves along the faces. Stems have a purplish cast in spring, change to medium green in summer and become yellowish in fall with lower stems changing to brown, as the epidermis splits with growth and stems become rounded. Woody dead stems persist into the next growing year.

Growth scars encircle stems and branches at base of petioles so that stems and branches are uniformly divided into 1 to 2-inch segments. Segment length remains fairly uniform all along stems and branches while stem diameter decreases slightly at upper ends of segments. Growth scars, which are purplish in mid-season, become brown in fall.

Cauline leaves (there are no basal leaves) grow from grooves along opposite flat sides of stem, with leaf pairs rotated 90 degrees from pair to pair. While lower leaves may be 4 inches or more long and 3/4 inch wide, upper stem leaves below the inflorescence may be an 1/8 inch or less long and inch wide. Leaves within the inflorescence become increasingly smaller to tiny and bract-like and tend to drop off in dry periods as flowering continues. Leaves are linear-lanceolate with very gentle tapers to blunt-tipped apexes and wedge-shaped (cuneate) bases. The taper to the leaf base is so gentle that separation of leaf blade from its short petiole is not especially discernable. Leaves have widely-spaced, shallow serrations which are clearly seen on large leaves but become obscure to absent on smaller leaves.

Inflorescences consist of terminal spikes on main stems and