19-07-2025
- Climate
- The Herald Scotland
Dorset Japanese Knotweed hotspots revealed for 2025
The invasive plant species is responsible for damaging homes, pavements and drains and can spread up to seven metres horizontally.
It begins to emerge in the spring and sticks around during the summer months.
There are currently around 100,000 known infestations of Japanese Knotweed, which can be found on the Environet interactive map here.
Japanese Knotweed is a highly invasive plant species (Image: Getty Images)
Environet Director Emily Grant said: 'By mapping verified sightings, we're helping people understand the level of risk in their local area and encouraging early identification and treatment."
She continued: 'Public engagement is key in the fight against knotweed, and by reporting new sightings homeowners can play an important role in controlling this invasive plant and protecting property values.'
Where are Dorset's Japanese Knotweed hotspots for 2025?
According to Enivronet, the worst spot for Japanese Knotweed in Dorset is around Lyme Regis, with there being 149 sightings within five miles of the DT6 6BW postcode.
Lyme Regis has a high concentration of Japanese Knotweed sightings (Image: Environet)
There are also large clusters around Dorchester (92 sightings within five miles), Weymouth (56 sightings), Wareham (42 sightings) and Swanage (33 sightings).
Alongside that, there is also a significant chunk close to Wimborne Minster with 60 sightings.
Within the BCP area, there have been quite a few cases of Japanese Knotweed, with 77 sightings reported within five miles of the BH12 2HB postcode.
Meanwhile, 62 sightings have been reported within five miles of the BH6 3LU postcode, taking in eastern Bournemouth and Christchurch.
The BCP area has a fair few cases of Japanese Knotweed (Image: Environet)
Highcliffe also has a fair few with 52 sightings reported within a five miles radius of the area.
How to spot Japanese Knotweed
Japanese Knotweed hibernates over winter, but in March or April, it begins to grow, with red or purple spear-like shoots emerging from the ground, which quickly grow into lush green shrubs with pink-flecked stems and bamboo-like canes.
The roots can grow as deep as three metres and spread up to seven metres horizontally.
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What to do if you have Japanese Knotweed
The first step to tackling the plant is to commission a professional Japanese Knotweed survey and find out the extent of the infestation. They will be able to tell you where it originated and the best way to tackle it.
Professional treatment should then be organised, which usually involves the use of herbicides for the excavation of the infestation.
If you're buying a property and you want to be sure it's clear of knotweed, particularly if it's located in or near a hotspot, arrange a detection survey.
