Photographs of Japanese knotweed

Japanese knotweed – deservedly - has a reputation for being a destructive plant. This invasive weed has the capacity to seriously damage property and buildings; being especially a problem if building construction takes place over an existing stand of Japanese knotweed. Indeed, such is its strength and vigour, shoots and rhizomes penetrate buildings, will lift concrete and paving slabs if allowed to grow unchecked.

Japanese knotweed growing through garden wall.

Japanese knotweed in summer. Tall shoots of between 2-3m height – a well established stand.

Japanese knotweed growing through floor of new building. The roof has only been on for a few weeks, when this picture had been taken

The destructive power of Japanese knotweed in a wall is clearly shown here

Japanese knotweed growing from under the building. Nearly 2m of shoots have emerged from the roof!

Japanese knotweed - shoots from a mature stand in early spring

Young Japanese knotweed shoots. This plant has been disturbed over the winter; these shoots are typical following disturbance.

A small crown of Japanese knotweed. Note the bud growing for the new season. This photograph was taken on a bitterly cold December morning in North Wales.

Japanese knotweed in flower.

Japanese knotweed in autumn. Shoots are senescing after the first frosts.

Japanese knotweed in winter. Shoots have died back to ground level. Dead shoots may still be standing for a further 1-2 years after dying.