This perennial plant is is usually ½-2' tall. The light green stems are terete, covered with appressed pubescence, and either erect or sprawling. The central stem is usually little branched, except near the apex of the plant, where the flowers occur. The alternate leaves are up to 2-3" long and ¾" across. They are lanceolate, elliptic, or oblanceolate in shape, while their margins are smooth (entire), dentate, or shallowly pinnatifid. Some leaves may have paired basal lobes. The leaves are either sessile against their stems or they have petioles up to 1" in length. Both the upper and lower leaf surfaces are light to medium green and either glabrous or sparsely appressed-pubescent.
About 1-3 flowers develop from the axils of the upper leaves. The appressed-pubescent flower buds are rather long and spindle-shaped. The showy flowers open up during the daytime, and they are 2-3½" across. Each flower has 4 broad petals, 8 stamens with white or yellow anthers, and a long white stigma that is 4-cleft at its tip, resembling a white cross. These flowers are usually pinkish white; they have fine pink lines that radiate outward from their throats across the rather wrinkled petals. The throats of these flowers are usually yellow. The blooming period occurs from late spring to mid-summer, lasting about a month, although individual flowers are short-lived. The flowers are replaced by elongated 4-angled capsules that contain numerous seeds. The root system is highly rhizomatous, forming sizable colonies at some sites.