Virginia buttonweed is an herbaceous perennial with prostrate or spreading branches. The stems are longitudinally ridged, especially below the nodes, with hairs along the ridges. The leaves are opposite without petioles and rough along the margins. The leaves are slightly thickened, green on the upper surface and light green on the lower surface with both surfaces smooth and slightly folded. The leaves of Virginia buttonweed often take on a mottled-yellow mosaic look due to a virus. The white flowers sometimes have pink streaks in the center and are borne in the leaf axil. Petals are united into a tube.