Japanese knotweed – Reynoutria japonica

Japanese knotweed is a fast-growing perennial herb in the family Polygonaceae. It forms dense stands which may reach up to 3 m tall. In its native habitat in Japan, it usually grows only 0,3 to 1,5 m in height.

Japanese knotweed thrives in a wide range of habitats. It requires light to grow and, therefore, it favors sunny habitats such as riversides, landfills and along roads and railways. It also grows in semi-shaded places such as forest clearings and edges, but rarely in forest. It also thrives on clayey and very barren habitats, and it is not demanding on soil acidity.