Plants That Look Like Japanese Knotweed

The spread of Japanese Knotweed on your land or property can be very damaging. With the plants rapid spreading habits, the time taken to remove it can increase dramatically and be very expensive.

The United Kingdom has a number of other plants that can be confused with Japanese Knotweed. This article by CYB Environmental will list some of the most similar plants to aid you in identifying a real knotweed infection. We are a RICS regulated company that specialise in the removal of Japanese Knotweed. For enquiries and assessments, be sure to contact us, we can help you decide whether or not you have a knotweed infection. That being said, let’s get into plants that look like Japanese Knotweed.

The Biggest Offenders

  • Bindweed
  • Himalayan Knotweed
  • Himalayan Balsam
  • Broad-leaved Dock

 

Bindweed (Convolvulus Arvensis)

With Bindweeds heart shaped leaves, it would take a closer inspection to gage whether or not it is Japanese Knotweed. The leaves of Bindweed are also similar to Knotweed due to the alternate growth patterns along the stem. Bindweed can also cover a large area very quickly if left untamed. One of that most mistaken plant that looks like Japanese Knotweed.

As the name suggests, Bindweed is a climbing plant that has the ability to grow by twisting around other erect plants. That being said, it is unable to support its own weight and lacks the ability to grow straight up, unlike Japanese Knotweed. Large pink or white flowers also appear in early summer for Bindweed, also distinguishing it from Knotweed.

 

Himalayan Knotweed (Persicaria Wallichii)

When not in bloom, Himalayan Knotweed can look extremely similar to it’s Japanese counterpart due to the similar stems. Not only to the eye, but also to the touch as the stem on both plants is hollow.

Take a close look at the leaves, are they very narrow and half as wide as they are long? With the stem growing to around 1cm in diameter? If so, the plant you’re inspecting is likely to be Himalayan Knotweed. The flowers have a pink hue, rather than the pure white plants on Japanese Knotweed.

 

Himalayan Balsam (Impatiens Glandulifera)

Similar to Japanese Knotweed, Himalayan Balsam is a rapidly growing plant. It can quickly cover a large area and grow as tall as 2.5 Metres. It also has a hollow stem.

Begin by inspecting the stem, you will see the leaves grow opposite each other, rather than the alternating pattern of Japanese Knotweed. The leaves are also much longer and thinner too, with a pink midrib.

 

Broad-leaved Dock (Rumex Obtusifolius)

Part of the same family, so hardly surprising that it looks similar to knotweed, Broadleaved Dock has leaves arranged alternately along the stem as well. Its flowers and stems also form spikes just like knotweed.

Stems are fluted and shorter than knotweed plants, growing up to 1m in height. The stems are not completely hollow and contain a foam-like substance when snapped open.