Phragmites (/fræɡˈmaɪtiːz/) is a genus of four species of large perennial reed grasses found in wetlands throughout temperate and tropical regions of the world. The Common Reed will bloom from late July to August, with purple to gold panicles of flowers. Seeds of this plant are grayish in color and have a fluffy texture with silky hairs covering each seed. Each plant can produce thousands of seeds each year. These seeds, however, have a low viability. communis phragmites Australis Seeds. Common reed is a large rhizomatous/stoloniferous cool season grass obtaining heights of up to 4 m (13 ft) with stems averaging 0.5 to 1.5 cm (0.2 to 0.6 in) in diameter. The leaf sheath is open. The ligule is a ring of hairs averaging. 1 to 2 mm (0.4 to 0.8 in) in length. Auricles are absent. The non-native Phragmites is a perennial grass that can reach over 15 feet in height. It is often found in dense clonal stands made up of living stems and standing dead stems.