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Japanese Knotweed Removal

Knotweed Control Services We Offer

We offer Knotweed Control and Removal Services in Dublin and throughout Ireland. Japanese Knotweed as a high invasive plant species must be managed by experienced professional experts. For a tailored quote or for more information contact 085 1699 592 or email

Japanese Knotweed causing problems around Ireland.

Japanese Knotweed invasive plant species are spreading and causing problems in our local rivers and streams, in gardens, and roadsides and also on construction/development sites.

As Irelands leading Japanese Knotweed removal experts, we specialize in the management and control of  knotweed plant species.

From general help and advice to understanding the damage that Japanese Knotweed plants can do. Our website is here to guide you through your Knotweed problem. We can advise and offer the Japanese knotweed removal and treatment solutions available to control the issue.

When considering the control or eradication of a highly invasive plant species in a defined area, a number of issues have to be taken into consideration.

On all of our site's we strictly follow industry guidelines and can draw up a ten point management plan. These plans help ensure compliance with relevant pieces of Irish and European legislation/directives as well as current best practice in the eradication & control of high impact invasive plant species. 




In 2012 the European Directive 2009/128/EC was transposed into Irish law.  The main reason for this Directive is to promote a more sustainable use of pesticides in both the farming and the amenity/landscaping sectors. One of the requirements in this Directive is to prepare a National Action Plan (NAP) for the sustainable use of pesticides. follow  the principles set out in this directive for example: Good Plant Protection Practice” (GPPP) which outline

basic principles of appropriate PPP use, and requirements for the keeping of records, along with proper storage of pesticides.



For more information on Pesticide Regulations in Ireland see:



An invasive Plant called Japanese Knotweed

How we can help you

Japanese Knotweed is a very tough plant and it is widely understood to be difficult to eradicate.

Knotweed Control Ireland are increasingly being asked to remove this plant from properties where others have failed.

Our technical expertise build up over the years working with this plant gives us a greater knowledge and understanding that home-owners, landscapers and builders just don`t have.

Do not take risks with Japanese Knotweed

Call us to arrange a site survey.


The Knotweed Code of Practice - EA, 2013

On the subject of On-site Bio-security.

On many sites unfortunately site hygiene regarding Knotweed bio-security is not taken seriously. 

If a site is not being properly supervised Knotweed Control Ireland with our experience can bring the site back in compliance with the Knotweed Code of Practice while keeping costs down to a minimum.

Note: Although the EA, Knotweed Code of Practice has been discontinued many experts in the industry still follow most of the relevant guidelines within this document.


Japanese Knotweed plant Flower

Our services cover Dublin & Leinster counties

Herbicide Treatment

The use of herbicide is often the most efficient and cost effective Japanese knotweed treatment option.

Used alone or as part of a combined Japanese Knotweed removal method, our “three way Japanese knotweed herbicide treatment system” allows the herbicide to reach both the tall Japanese knotweed foliage as well as the rhizome/root system that can grow up to several meters under ground.

The main issue is whether or not the Japanese knotweed is near a water source. If this is the case, other non-residual removal options have to be applied these are recommended by Best Practice Guidelines. Depending on the size of the infestation It does however, typically need 3 to 5 applications before becoming effective. By organising a Japanese knotweed survey, a surveyor can inspect your property and advise the best Japanese knotweed removal method.


A Note to Land Developers

If you are looking to buy or sell development land you should be aware that Japanese knotweed may reduce its value.

The reduction in value is normally calculated based upon the cost of remediation plus the risk factor for the inherent risks associated with developing knotweed affected land.

Typical risks include;

  • Difficulty in securing external funding on land affected by knotweed

  • Delays caused by planning objections from aggrieved neighbours

  • Civil nuisance claims by adjoining owners for knotweed encroachment

  • Increased costs and delays to construction

  • Saleability of the developed land

  • Litigation risk post sale

Note: All of the above depend on site conditions including size of Knotweed infestation and typically apply to large infestations, as small infestations can generally be eradicated with minimum impact.


However, a good knotweed specialist can provide the key to maximising the development value by finding the most suited and cost-effective remediation method, and by helping to manage the inherent risks.


Herbicide is the most cost-effective control method. However, it takes repeated applications needing at least 3 -5 years to be fully effective. It’s an accepted method if ground is not to be disturbed, and some regrowth can be tolerated.


Total excavation of the root and rhizome system is a more robust method for development land, because it’s quicker and more effective. However, it’ may become expensive, especially if there is a large infestation on-site.

Delays in construction programmes cost money. Unfortunately, Japanese knotweed remediation is not a precise science and in-experienced companies new to the invasive plant business can soon realize that things can go wrong. 

Common examples include encountering groundwater, ground contamination, below ground obstructions such as live services, all of which increase costs and can result in time delays.

For residential developments nearing completion, savvy solicitors acting for buyers will ask whether the site is or was previously affected by knotweed.

The developer will need to disclose the facts or risk future litigation. The buyer, backed by his solicitor and lender, may demand a copy of the site Management Plan including all associated reports. If these can’t be provided or are not compliant to current Best Practice (PCA - KCoP, 2018), and related legislation (S.I. 477, 2011) it’s likely the sale will stall.

A developer who does not disclose to a buyer that the land was affected by Japanese knotweed puts himself at unnecessary litigation risk. If Japanese knotweed emerges, the buyer as the new owner will be annoyed, and ask the developer to put things right. The new owner may also decide to claim for diminution in value.

If however the developer discloses that knotweed was present and can show there is a current eradication/control program in place. The developer in this instance should be better protected from any litigation risk.

See: S.I. 477, 2011 under Section 49 -The section also provides for a defence (if it can be proven) that the accused took “all reasonable steps and exercised all due diligence to avoid committing the offence”.

There are other alternatives, notably Soil Screening 

whereby infested soils are processed on site to remove the viable rhizomes and other visible contaminants.


The soils are re-used on site, thereby avoiding the excessive costs of off-site disposal and import of clean fill material. This method typically costs half that of disposal to landfill.


You might think that having commissioned a specialist to get the site remediated is the end of your knotweed problems. Unfortunately that might not be the case, as risks remain that need to be managed.


It’s not uncommon to find neighbours trying to frustrate development by objecting to planning. Whilst this tactic is unlikely to succeed, it may result in the imposition of a planning condition that will need to be discharged prior to commencement on site. Knotweed Control Ireland will be able to assist.


Japanese knotweed does not respect property boundaries. Encroachment, the spread from one parcel of land to another, is common. Aggrieved neighbours are increasingly resorting to litigation to resolve such issues, so it is vital that action is taken early to prevent or at least mitigate the risk to provide a strong defence to counter any expensive claim.


Knotweed Control Ireland was the first company in Ireland to offer clients a complete Knotweed eradication/control service, covering the inclusive range of Best Practice methods  from Herbicide Application, Bunding, Root Barrier Installation, Soil Screening & Burial on/off site.

The law concerning Japanese Knotweed in Ireland




There are approx. 35 plant species listed in the third schedule (Part 1) to these regulations, while a number of animals are listed separately in (Part 2).

Schedule three (Part 3) also specifies a prohibition on the movement of vector material with specific reference to “soil or spoil taken from sites infested with Japanese knotweed.

Invasive species logo to help stop spread
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