The Enemy Within, at the RHS Chelsea Flower Show

The Enemy Within, at the RHS Chelsea Flower Show

The RHS Chelsea Flower Show is the most famous flower and landscape garden show in the UK (and possibly, the world!). This year Lancaster University PhD researcher Claire Holden has provided several sets of invasive ‘alien’ species, such as Japanese knotweed, giant hogweed and Himalayan balsam. These have been cultivated in university greenhouses before being securely transported for display at the show as part of the Property Care Association exhibition stand, which is titled ‘The Enemy Within – Managing Invasive Plants’. This is located within the show’s ‘Discovery Zone’ and aims to highlight to the public the dangers of allowing invasive non-native plant species to grow in and spread from their gardens.

Claire is a PhD graduate researcher in the Centre for Global Eco-Innovation, an award winning initiative which brings together the expertise and facilities of Lancaster University with regional SMEs to tackle environmental and societal challenges. Based at the Lancaster Environment Centre, Claire’s research is a collaboration between Lancaster University and Phlorum Ltd. Phlorum is an environmental consultancy providing services with expertise in evaluating and mitigating Japanese knotweed property risks, including guiding the Royal Institution of Chartered Surveyors.

“We had to get special licences before we could start growing the Himalayan balsam, so it wasn’t simple” said Claire Holden, PhD Graduate Researcher.

Invasive species can damage property and cause huge disruptions in the housing market. Current excavation and herbicide control methods can be both costly and environmentally damaging. Claire’s PhD research will help Phlorum to understand why Japanese Knotweed grows so quickly and profusely and give a fuller understanding of the biology of this invasive species. Japanese knotweed is one of the world’s 100 worst invasive species, causing crop losses, damage to infrastructure and erosion of ecosystem services. Current control methods are expensive and offer limited success.

“If we understand more about the biology of this species, we might understand why it grows so quickly. This could allow us to identify more effective solutions to inhibit such rapid growth rather than just using herbicide on it, which is what happens at the moment” Prof Jane Taylor, Lancaster Environment Centre.

Dr Paul Beckett from Phlorum adds, “The impact of knotweed on property transactions could eclipse the £165.6 million per annum cost that is often quoted for its control in the UK. This is because the weed’s blighting effect can reduce property value by as much as 5% to 20%, which is being found in the numerous litigation cases that have recently been settled or judged in the courts. This does not tally with the relative absence of good quality research on understanding the biology and ecology of this unique and economically important weed. We are therefore bound to find valuable insights from Claire’s research that we hope will lead to further collaboration with Lancaster University and hopefully to novel methods to effectively deal with this pernicious weed”.