Japanese knotweed is a significant problem and can cause serious issues for a home. Here are some tips on how to get rid of this terrible weed.
1. Getting Rid of it Yourself
Japanese knotweed is such a common plant that you may think it must be easy to kill it yourself. Many people have tried it and some managed to have some success. However, there are many complex legal issues related to the impact of knotweed on a property that any DIY effort may have potentially costly legal consequences.
In fact, the need by banks and building societies to professionally manage the risks associated with knotweed has led to the formation of a Contractor’s Trade Body and detailed guidelines for surveyors. This could be of particular interest to you if you are in the process of buying or selling a property that is affected by knotweed.
Incidentally, it need not actually be on your property but if there is knotweed growth on a neighboring property it could affect your property too. (Read our blog post on buying a property affected by knotweed). However, if the risks are not high enough to cause concern, there are still a number of ways to kill knotweed on your property or at least reduce its spread significantly.
2. Herbicide Treatment
A wide range of herbicides are readily available to the general public and you will be able to purchase these products at your local garden center. When using herbicide products it is important to follow the instructions carefully and check the expiry date.
The active ingredients in certain products may have been withdrawn from public use so it is always safest to buy products that are in date and specifically intended for the eradication of weeds. Most herbicide products list the plants that can be treated on the label, just make sure that the Japanese knotweed listed is one of them.
There are products available that are much stronger than those distributed to the general public, however, they are only available to professionals who have passed a series of exams and have been trained on how to apply them. For this reason, DIY treatments can take years longer to produce results than those achieved by professional applications.
3. Digging it Up
The main methods of dispersal that have led to a proliferation of knotweed across North America, Europe, and the UK are:
- The generation of rhizome fragments caused by soil excavation close to and even several meters away from knotweed plants;
- and their potential of spreading in the soil arisings.
For this reason, special care should be taken in situations where there may be a risk of disturbing or fragmenting knotweed rhizomes. Due to the ‘iceberg nature of the extensive and wide-spread rhizome system of Japanese knotweed, this can easily be done without realizing it. If you inadvertently spread knotweed propagules you may be at risk of breaking the law or exposing yourself to litigation.
Having said that, if you are prepared to take the risk, the best way to immediately kill the weed is to dig up the rhizome system. However, dealing with the fragments can be even more problematic. Ideally, they should be removed from the site and safely disposed of at a licensed waste facility. A skip hire company will be able to take care of this, but you can expect to pay a hefty amount per load. Extra special care needs to be taken when handling the weeds to ensure that no rhizome fragments are left behind that will quickly spread again.
There is a range of other removal options that professionals use after excavation, including burial and screening, but these methods are not recommended for DIY projects.
4. Professional Help
We realize that it may be tempting to tackle the problem of a Japanese knotweed infestation on your own considering it is after all just a common plant. However, when considering the potential risks of litigation, prosecution, and diminished property value, it becomes a much less attractive option. If you have any doubts, the best thing is to gain peace of mind by hiring a professional company with established credentials and qualifications to deal with the problem.
We were one of the founding members of the trade body established in consultation with the Building Societies Association and the Council of Mortgage Lenders to deal with the potential property risks associated with Japanese knotweed. Environet specializes in providing a full range of solutions including surveys, legal advice, consultations, and ‘boots-on-the-ground’ site works.