Is this Japanese Knotweed?

There are many plants which can appear like Japanese knotweed. Japanese knotweed is one of the most misidentified plants, which can lead to costly errors for homeowners or mortgage advisors further down the line. While we would recommend getting a certified surveyor to your property to examine any suspected Japanese knotweed growth, but here are a couple of signs that you can use to help you.

In The Spring:

Japanese knotweed will start growing from March or April. The new shoots are a dark red, almost purple colour. As the leaves start to unfurl, they may have a reddish tinge. The leaves will otherwise be light green in colour, appearing as fresh new growth.


In The Summer:

japanese knotweedJapanese knotweed will grow heart-shaped leaves. The stems will be green whilst they are growing and will develop purple speckles later in the season. In late summer, white flowers will appear.


In The Autumn:

The flowers will die off. The leaves will turn yellow in colour before dropping off the plant. The dead stems will become cane-like and will turn brown before dying away completely.


In The Winter:

japanese knotweedThe stems will appear hollow and woody. The stem can persist in your garden for up to two years after the leaves have dropped. If the stand has been there for several years, the stand may become black and knobbly over time.


After Treatment:

If the plant has been sprayed, the knotweed may look like knotweed as pictured in winter or autumn. The leaves will die off, but some may remain attached to the plant depending on the season. The stems will appear woody. If the plant has not been fully eradicated, new green growth will appear quickly, especially in spring or summer.

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