A recurring nuisance to gardeners across Britain has been the introduction of a fairly persistent little bugger known as Japanese Knotweed. Originally introduced by the Victorians as an ornamental garden perennial, this invasive plant broke into the news recently for completely undermining the structural stability of one Hertfordshire couples home, along with its retail value. Matthew Jones and Sue Banks were told that, after a particularly virulent specimen of Fallopia Japonica had burrowed through the concrete of their living room wall, the financial worth of their property had fallen by a quarter of a million pounds. The Environment Agency recognizes Fallopia Japonica as a national threat to garden welfare, as it rivals bamboo in its growth rate, and most rabbit warrens in its ability to procreate! The species can increase in length by over 10 cm a day and, as the Hertfordshire case demonstrates, is not discouraged in the least by hardened materials such as paving, brickwork or even solid concrete.
In 2009 a government study revealed a potential cure to the weed, a jumping louse of similar origins to the weed itself, known as Aphalara Itadori, which is believed would see the decline of the plant with a mass devouring of its sap. This study aptly referred to the Knotweed as a real life equivalent of a Triffid and, as such, a menace to horticultural society – able to grow up to 7 m horizontally and 5 m metres underground, completely regenerative from any particle exceeding the dimensions of a drawing pin and capable of drowning smaller flowers and native species in its foliage. However, the body was understandably reserved about releasing Britains first deliberate biological control, particularly in the wake of the North Australian cane toad disaster. Questions were raised as to how our environment might sustain the jumping lice, were they successful in wiping out Knotweed.
Fast forward to today and, while the louse is yet to be release on a mass scale, there are still a variety of different techniques that the environment agency recommends, should you notice your own garden falling prey. Of course the first step is decisively identifying the menace in time to combat it – first and foremost the rate of expansion will be unlike most anything else youve come across, marching forward like a lush green platoon it will conquer new ground daily. The foliage itself is shovel shaped and will be supported on a cane similar to bamboo. Finally, you have the white flowers produced September October and the trademark colourful autumn foliage.