Ipswich has by far the largest number of Japanese knotweed infestations in Suffolk, figures have revealed.

The data comes as the invasive plant returns from a winter hibernation – posing risks to property owners by knocking as much as a tenth off house prices.

The plant can grow up to three metres in height by mid-summer, pushing up through concrete, driveways, drains and the walls of houses.

Data compiled by company Environet UK on their "Exposed" tracker has found Ipswich tops the rankings for the most infestations in the county, with 41 recorded within a 4km radius.

Ipswich Star: A map of Japanese knotweed infestations in Suffolk and north EssexA map of Japanese knotweed infestations in Suffolk and north Essex (Image: Environet UK)

The figure is 70.8% higher than the next highest, Lowestoft, where 24 infestations were recorded.

Stowmarket ranked third-highest with 16 infestations, while Bury St Edmunds and Aldeburgh were both found to have 8.

Mat Day, Environet’s regional director for East Anglia, said: “Knowledge is power when it comes to Japanese knotweed and this heatmap is invaluable to homeowners and buyers who want to assess the risk in their local area.

"With the stamp duty holiday extended and lockdown restrictions beginning to ease, the property market is busier than ever – but failing to carry out the appropriate checks for knotweed can turn out to be an expensive mistake.

“Despite its fearsome reputation, with professional help, the plant can be dealt with and the value of a property largely restored.

"I’d urge anyone buying or selling a property, or homeowners wishing to preserve the value of their home, to be vigilant for signs of spring growth and check Exposed to see whether they live in a high-risk area.”

Made popular in the UK by the Victorians, the weed was first brought to the UK in the 1840s – although allowing the weed to spread can now see property owners slapped with a fine of up to £5,000.

Approximately £166m is spent every year on treating the plant in the UK, with the government estimating it would cost as much as £1.5bn to clear the country of knotweed.

Those who spot an infestation, characterised by the plant's purple or red asparagus-like shoots, can mark it on Environet UK's online map, with each photo verified by experts.

The map can be found here.