The most invasive plants found in the UK

Homeowners warned invasive plants could be lurking in their gardens

Households have been advised to undertake a winter purge to rid their gardens of any invasive plant species which could cause havoc next summer if left unchecked.

Ecologists from Arbtech have identified eight species of non-native plants that have become widespread in the UK and which can cause issues if left to grow unchecked.

The experts say even the most diligent gardeners can fall victim to an invasion of these species, but identifying and dealing with these invaders now will mean they’ll be less likely to become a nuisance next spring.

Japanese Knotweed is probably the best known invasive species and can present a real headache for homeowners. But there are other invasive species that are widespread and often found in residential gardens such as Giant Hogweed and Himalayan Balsam. These species are listed on Schedule 9 of the Wildlife and Countryside Act (as amended) 1981, which makes it an offence to cause the spread of these species, due to the risk posed to native floral species.

The 8 biggest plant invaders of UK gardens

Giant rhubarb (Gunnera tinctoria)

Curly waterweed (Lagarosiphon major)

Floating pennywort (Hydrocotyle ranunculoides)

Giant hogweed (Heracleum mantegazzianum)

Himalayan balsam (Impatiens gladulifera)

Japanese Knotweed (Polygonum cuspidatumi)

Parrot’s feather (Myriophyllum aquaticum)

The experts from Arbtech have also named a further 27 species of non native plants which, while not yet fully widespread across Britain, still pose a hazard to gardeners in many parts of the country.

These include Alligator Weed, Balloon Vine, Persian Hogweed and the inappropriately named Tree of Heaven.

Arbtech’s experts say anyone planning to develop land should consider doing a full invasive plants survey to discover exactly which species are present so they can reassure planning officers that they won’t pose a problem.

A spokesperson for Arbtech said: “There are many invasive species of plants which, while not native to the UK, have managed to establish themselves here over many years.

“By their very nature these plants are usually fast growing and are able to spread vigorously.

“Left unchecked they can create all manner of problems for homeowners from structural damage to presenting a potentially lethal threat to pets if eaten.

“They are usually viewed as weeds although some of them can appear quite attractive and many gardeners can be forgiven for confusing them with flowers and not realising just how much of a problem they present.

“Council planning departments are generally aware of the threat these invasive plant species can present and many will insist on a survey that determines the potential for impacts to invasive species before granting planning permission for a scheme to ensure any invasive species have been identified and dealt with appropriately.

“By naming the eight most widespread invasive plant species along with a further 27 species we believe households should be on the lookout for, we hope to be able to help gardeners identify issues before they become too problematic.

“These plants can get a toe-hold anywhere and often aren’t spotted until they have begun to spread exponentially across a garden and even a neighbourhood.

“By visiting the invasive species page on our website, concerned people can identify if the weeds they have found in the garden really are invasive.

“If you are planning a development and are concerned about invasive species our ecologists are available to conduct full surveys which will help with your planning application.”

To read more about the eight most widespread invasive species and to see the full list of the 27 other invaders households should look out for, please visit: https://arbtech.co.uk/ecology-surveys/invasive-species/