Identifying Japanese Knotweed
APSL Japanese Knotweed – How to identify Japanese Knotweed in Ealing, Chiswick, Acton and Greater London
Please find below characteristics of Japanese knotweed that could help identify knotweed throughout the year. If you do suspect you have knotweed, attach a photo to our online survey form and email this for a free knotweed identification. If you are unable to send an image please call or complete the form below to arrange a site visit and we will get back to you as soon as possible.
Knotweed Early Spring
In early spring, look out for bright red/purple shoots appearing from the ground. Small knotweed leaves are rolled up and start to unfurl as the cane rapidly grows. The leaves become greener as the canes get taller. Even though the plant is small it could be part of an extensive rhizome network underground so do not dig it out.
Knotweed Early Summer
As Japanese knotweed starts to mature, the tall bamboo like hollow canes are green with a distinctive purple speckle.
The green leaves are shaped like a pointy spade and grow in a zigzag pattern from the stem.
A mature knotweed cane can reach a maximum height of 2 to 3 metres in a growing season.
Mature Japanese knotweed canes can grow very densely together.
Knotweed Late Summer
Later in the summer, from around August to October, clusters of creamy white flowers appear on the plant. These provide a great source of nectar for insects so look out for an influx of insects to your garden when identifying Japanese knotweed in the summertime.
Knotweed Winter
During autumn, the knotweed leaves will start to discolour and fall from the plant.
As the frost appears, the canes will die back. The hollow bamboo like canes turn brown and can become brittle but most stay standing throughout the winter months. Occasionally the old canes can be found amongst the new stands the following summer.
