Flowers: clustered loosely in a panicle. Calyx: swollen; reddish, sticky, with five lobes. Corolla: of five deeply fringed petals. Stamens: ten; ex-serted. Pistil: one; styles, three. Leaves: sessile; lanceolate; whorled in fours, or opposite in pairs on the upper and lower part of the stem. Stem: two to three feet high; reddish coloured.
The deeply fringed petals and yellow-green leaves of the starry campion form masses of delightfully cool colouring that seem to breath the freshness of the midsummer woods. It is in the evening that the flowers unfold, although in much shaded woods they remain open until noon of the next day. The plant is a conspicuous catchfly.