The problem with Japanese knotweed, is that despite the fact it dies back throughout the winter, its root system is both extensive and strong.

The roots are the only way in which the plant can spread, as it doesn't produce seeds.

This vigorous characteristic has resulted in it being an offence against the 1981 Wildlife and Countryside Act to grow it, and if it isn't controlled by those who have it in their garden, a community protection notice can even be given.

In terms of control, Japanese knotweed is obviously extremely difficult. Digging the weed out is certainly the most environmentally friendly method; however it is back breaking work considering the roots can travel so far and that the smallest rhizome can produce an entirely new plant.

In terms of chemical sprays, Glyphosate is the most viable option. Applied to the leaves, it is absorbed by the entire plant and is capable, after a few years, of killing this troublesome weed.

A relatively new option however is biological control using psyllid (plant sucking bugs). Currently on trial, if this method proves successful, hopefully it will be offered to gardeners up and down the UK.