Homeowners are being urged to be extra vigilant of Japanese knotweed growing on their properties after the invasive species emerged six weeks earlier than usual this year following unusually warm weather. The distinctive red stems were spotted throughout February and March, a development which has been linked to climate change.
England and Wales had their warmest February on record this year, with mild and wet conditions common. The Property Care Association (PCA) reported that this allowed the plant to thrive, and that stems had been spotted well ahead of the start of the usual growing season in April. Ben Lindley, of Japanese Knotweed, a specialist in tackling the plant, says it tends to appear from its winter hibernation earlier in warmer weather.
The prospect of the plant growing on a property can strike panic in homeowners due to its potential to damage driveways and patios, hinder surrounding plants from growing and spread rapidly – as well as the expense of getting rid of it. Originally introduced in the mid-19th century as an ornamental garden plant, it costs the economy almost £250 million a year to tackle as it grows on roadsides, riverbanks and derelict land.
Anyone selling their property has to declare on a form whether or not the species is present. Answering untruthfully can result in legal implications, as can allowing it to spread to neighbouring properties without treatment. Daniel Docking, of the PCA’s invasive weed control group, says people who spot it should seek help quickly in order to manage the problem.
Getting rid of knotweed can be a lengthy and costly process. The simplest way is to apply herbicide over a long time, taking between two and three years of treatment, costing between £2,000 and £3,000. It can be instantly eradicated by excavation, but costs can spiral to between £5,000 and £15,000, with terraced houses typically proving even more expensive. The Property Ombudsman says sales can fall through because of the plant.
