Stem Cell Injection - Japanese Knotweed

By LoopZillaStem cell injection is a fairly recent and very effective method of dealing with and treating an outbreak of Japanese Knotweed.

Stem Cell Injection is a revolutionary development, which has been greatly improved the last few years. Advancements in the technique and specialist equipment used in the process have resulted in a more effective treatment, so much so, that Stem Cell Injection is now considered by many to be the best method for Japanese Knotweed eradication.

How it Works

Stem cell injection works by injecting Glyphosate herbicide into each individual plant using specialist equipment, a process which may be particularly familiar with Gardeners and Horticulturalists.  This process uses the plants own natural mechanisms to transport and spread the herbicide through the plant.

Stem cell injection offers many benefits over traditional alternatives such as dig and dump and spray applied chemical herbicides.


Unlike traditional sprayed herbicidal treatments, Stem Cell Injection is localised and can be applied with minimal impact on its surrounding environment.  Stem Cell Injection does not suffer the risk of drift spray, avoids contamination of water courses and loss of other plant species. This is particularly important in natural wildlife areas and within conservation and or protected areas.

The process is direct and reasonably fast acting, able to treat clumps of Japanese Knotweed in minutes and by targeting the stem and roots, can result in an unusual green tip characteristic, with the ends of the plant being the last areas to be affected by the herbicide.

It can be applied with relatively little expense, either by trained professionals, or through DIY self-taught kits, although it should be noted, that it is likely the DIY kits may not satisfy Estate Agents whom require a certification to sign off the completed process.

Costs are kept low, as there is no requirement for disposal in specially contaminated tips, as once the plant is dead, it is no longer considered to be a contaminant.


The main drawback with Stem Cell Injection is that it is labour intensive; as such the cost and time to deliver and inject individual plant stems may prove costly. This may be more prevalent on large sites, with an extensive Japanese knotweed outbreak, where on site burial may be a more viable option.


There are few limitations with Stem Cell Injection; however the process is most effective when the treatment can be applied directly to the centre of the plant, particularly when applied early on in the Japanese Knotweed outbreak.

Stem Cell Injection may be limited in its effectiveness where the evasive plant has spread into wall cavities, under floors and in service pipes etc. As such, it may be worth seeking advice of an approved specialist to undertake a survey. Stem Cell Injection may also be used in conjunction with other remedial treatment.

Other considerations

It the Japanese Knotweed has spread into neighbouring gardens, this would require permission of the adjacent owner, before any treatment is carried out.

 It is also an unlawful offence to permit (whether unknowingly or not) the spread of the plant onto neighbouring land and is considered a nuisance under Common law.

Further Advice

If you suspect Japanese Knotweed may be present, you should obtain professional advice immediately.