With the Japanese knotweed growing season well underway, invasive plant specialist Environet has revealed this year’s Isle of Wight knotweed hotspots.
The lists comprised the latest data from its online tracker, Exposed: The Japanese Knotweed Heatmap.
According to the figures, there are a total of 554 verified knotweed sightings on the Isle of Wight (3.77 incidences in every 1mi²).
In the national Japanese knotweed hotspots list, it’s the eighth worst affected county in England.
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Japanese knotweed hotspots on the Isle of Wight. (Image: Contributed)The Isle of Wight’s Top 10 Japanese knotweed hotspots for 2025 are as follows:
Shanklin – 79 incidences
Newport – 78
Ventnor – 66
Bembridge – 49
Ryde – 36
Sandown – 31
Cowes – 30
Freshwater – 29
East Cowes – 25
Brading – 11
Japanese knotweed first arrived in UK in the Victorian times, in a box of plant specimens delivered to Kew Gardens, and was quickly adopted by gardeners and horticulturalists, who were unaware of its invasive nature.
Since then, it has spread widely, with an average of 1.1 occurrences in every square mile of England.
Knotweed begins to emerge in early spring, quickly growing into lush green shrubs with pink-flecked stems, heart-shaped leaves and bamboo-like canes.
It can pose serious problems for homeowners, with underground rhizomes emerging through cracks in concrete, tarmac driveways, pathways, drains and cavity walls.
A 2023 DEFRA report put the cost of tackling knotweed to the UK economy at nearly £250 million a year.
AloJapan.com