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Japanese Knotweed

In the Parish of St. Martin we are blessed, or perhaps that should be cursed with an invasion of Japanese Knotweed. This pernicious pest was originally brought to the Island by the Victorians, who thought it an attractive way of covering unsightly areas quickly. It certainly covered the areas quickly for them but then refused to stop growing and spreading. It can grow up to 9’ tall and grow in the most difficult of conditions, even penetrating concrete and tarmac. It is almost, but not quite, impossible to kill but here in St. Martin, we are doing our best to eradicate it. If we do not, then within a generation we will find that it will have taken over most of the cliff land in the South East of the Island and its root system will result in erosion and us losing all other flora from our beautiful cliffs.

The St. Martin’s Douzaine have got together a group of volunteers to wage war on this pest and the first battle is being waged below the tea rooms in the Moulin Huet valley. This area is arguably one of the most beautiful in Guernsey and until about 10 years ago was a mass of blue hydrangeas shrubs interspaced with a number of Willow trees. The Willows have now gone and the Hydrangeas are few and far between but are desperately making a last stand against the all conquering Knotweed.

Our hardy band of volunteers has, over the winter removed all the Knotweed we could find and have burnt it. Just a few weeks ago the area was completely clear, at least above ground, of the stuff. Within the last four weeks it has re appeared and has grown at least 18” in height. Another working party within the past few days has got rid of the stuff again….but…there is no doubt whatsoever that within another few weeks it will be back. All we can do is to dig it up and burn what we can and spray with chemicals over the growing season.

If you any person reading this is able to visit this site, you can see for yourself the task we have set ourselves and remember. This is just one of a number of infestations throughout our lovely Parish.


If any person reading this knows of the whereabouts of any Knotweed. Please contact the office on 238363.

We may not be able to help…but…we will do our best.

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