Flower:

Usually a single cluster of a few to several flowers tightly grouped at the top of the stem, surrounded closely by two pair of opposite leaves of unequal size. Flowers are 1 to 2 inches long, tubular, with 5 short blunt tipped lobes that are erect revealing the narrow tube opening, or folded in over the mouth of the tube, closing it. Color is pale greenish/violet to white or gray tinged with blue. Short lance toothed sepals surround the base of each flower.

Leaves and stems:

Leaves are opposite, typically light green, generally lance-shaped, rounded at the base, tapered to a sharp point at the tip, stalkless, surfaces and edges smooth and glossy, typically 1½-3 inches long and about 1/3 as wide, though the upper leaves tend to be broader than lower leaves. Stems are simple, smooth, often red.

Notes:

A similar species is Bottle Gentian, (Gentiana andrewsii), which has flowers with much deeper color and remain closed, its overlapping flower lobes rounded with fine teeth at their tips. Great Lakes Gentian is far less common, only known to be present in Minnesota, Wisconsin, Michigan and the Canadian provinces bordering the Great Lakes, plus a few counties in Maine and in New Brunswick.