How to identify Japanese Knotweed
Japanese knotweed is easily identifiable through its distinctive leaves and flowers. It’s flower is white and looks a little bit like a buddleja.
Please have a look at our gallery to see examples of Japanese Knotweed.
In spring and summer, bamboo-like shoots grow to 2.1m (7ft) tall. Leaves are up to 14cm (5½in) in length and the creamy-white flower tassels produced in late summer and early autumn reach up to 15cm (6in).
The plants become 100% developed by the early summer season and very old stalks are hollow inside with very obvious dark purple spots and form thick shoots that grow up to three metres high. Flowers grow in late summer and these consist of groups of sharp spiky stalks with small creamy-white flowers all over them. These are a great source of nectar for insects such as bees and wasps. Japanses Knotweed seeds are not very fertile and in the UK, it spreads the most by vegetative means.
The helpful BBC video demonstrated how to identify and treat Japanese Knotweed
In late autumn the leaves will fall to the ground and the cane becomes dark brown in colour. Japanese knotweed remains dormant over the winter months.
The stems die back to ground level in winter. Japanese knotweed likes to grow in all conditions and in many terrains. This is the problem. In winter Japanese knotweed can look like it’s dying off underneath it is still very much alive.