The leaves of rose campion are noteworthy for their dense white hairs covering both the basal and stem leaves. The basal leaves, measuring 3 to 5 inches (7.6 to 12.7 cm) long and 1.5 to 2.5 inches (3.8 to 6.35 cm) wide, are inverted, lanceolate, spoon-shaped, and exhibit a grayish to silvery green color. Stem leaves, oppositely arranged with 5 to 10 pairs, are 2 to 4 inches (5 to 10 cm) long and 1 to 2 inches (2.5 to 5 cm) wide, becoming smaller upwards. Both types exhibit a stiff, leathery texture with entire margins.

Rose campion features flowers that measure 1 to 1.25 inches (2.5 to 3.2 cm) in diameter, either solitary or in small clusters of 2 to 3. The 5 obovate-orbicular petals are reddish purple, pink, or white, with irregular and slightly notched margins, appearing floppy and overlapping. A whitish-green calyx, densely covered with white-wooly hairs, measures 0.75 inches (1.9 cm) long. The flower has 10 stamens and an ovary with 5 styles. Flower stalks are 0.5 to 6 inches (1.3 to 15.2 cm) long with white-wooly hairs.

The stems of rose campion are erect and stout, typically branching toward the top. They exhibit a grayish-green to white coloration, owing to dense woolly hairs that cover them. Each stem ranges from 16 to 40 inches (40 to 100 cm) in height, contributing to the plant’s overall robust appearance. The thick, woolly texture is a key identifying feature, creating a distinctive grayish hue that can help differentiate rose campion from other species.

The fruit of rose campion manifests as a capsule that takes on an ellipsoid to ovoid shape, roughly 0.5 inches (1.27 cm) in length. Each capsule reveals a quintet of teeth at the opening, through which numerous diminutive, kidney-shaped seeds emerge. These seeds, less than 1.5 mm in size, are densely packed within the capsule. The coloration and texture specifics are not provided, but these capsules facilitate the self-seeding process of rose campion, ensuring its propagation.