Email us if you need assistance or see our useful F.A.Q’s. Live chat is also available but bear with us as staff levels are currently low. Email us at

Request a callback

Live chat

Request a sample

Japanese Knotweed: Can we proffer a solution?

Japanese knotweed is commonly known as Fallopia Japonica.


It is a perennia plant from the Polygonaceae family from Eastern Asia. Japanese knotweed has hollow stems with distinct raised nodes that give it a look of bamboo, even though it is not closely related. Knotweed stems can reach a height of three to four metres and the roots (Rhizomes) can extend the same in to the ground and up to seven metres horizontally making eradication of this invasive species difficult. The way to treat the problem is to cut down the upper foliage and then remove the root structure, then dispose of the excavated material in a responsible manner, then the roots are treated and covered with a strong enough material that would not easily puncture. Concrete has been used but is obviously expensive and labour intensive. However leaving even the slightest gap will allow the plant to regrow swiftly.

So, what is our answer at Ecogrid? Well we need a solution that is both cost effective and swift to install. We suggest the following: • Cut down the foliage and excavate to two metres to entire area. Remove spoil in a controlled manner. • Spray the area with sea water • Cover the ground level with a thermally bonded 200 g membrane • Cover the membrane with a LDPE Visquene layer • Lay Ecogrid e30 recycled plastic grids over the surface • Re-level ground conditions Explanations: • Sea water has been proven to be an effective way of controlling the Rhizomes • A thermally bonded membrane has proven to be a highly effective barrier with an efficient cone drop efficiency or puncture resistancy • The LDPE membrane creates a light barrier that is relatively non-penetrable, especially when covered with Ecogrid which will reinforce the LDPE layer. Ecogrid tiles come pre-locked with our patented locking mechanism in the form of 12 tiles pre-assembled making fitting very simple.


Leave a Reply

Sorry, you must be logged in to post a comment.