How to Identify Japanese Knotweed
Japanese Knotweed is easily identified by its large green oval-shaped leaves and bamboo type stem.
Spring
During March to April the plant sends up new shoots; red-purple in colour with rolled back leaves.
Summer
The plant is a perennial with distinctive branching, hollow, bamboo-like stems covered in purple speckles, often reaching 2-3 metres in height.
The leaves of the mature plant are up to 120mm in length with a flattened base and pointed tip and are arranged on arching stems in a zig-zag pattern.
Late Summer
The plant flowers late in the season, August - October with small creamy white flowers. Although seeds are produced they rarely survive.
Winter

During Winter the leaves die back to reveal orange/ brown coloured stems which may stay erect for several years. Stem and leaf material decomposes slowly leaving a deep layer of plant litter.


