While the idea of “criminal plants” may sound far-fetched, these invasive flora could land you in a lot of trouble
The little-known plant law leaves many strung out.(Image: Getty Images/iStockphoto)
People with green thumbs are often very protective of the plants in their garden, many seeing the foliage as friends. So facing having to get rid of some of them, can be a sore subject for some.
But the regulations that have been put in place have been done for public safety. Several plants you could see up and down the country are actually illegal to cultivate.
The plants are typically invasive species that can go after native species in our wild green spaces. Either that, or they pose a danger to animals and humans alike.
A local gardening company spoke to the Express, and said: “These plants tend to spread vigorously, making their control costly and difficult. Fines and regulations would apply to anyone who fails to abide by the law.”
And even native species can prove harmful, with Terry Smithson, Biodiversity Manager and Ecologist at Bioscapes, saying that plants “like ragwort and creeping thistle are recognised as harmful under the Weeds Act of 1959 as they can become a problem to farmers or for livestock”.
However, he noted: “Being native species, they are rarely a problem in natural habitats and, indeed, are a valuable component of the ecosystem. Ragwort for example provides a valuable source of nectar for many insects and the beautiful cinnabar moth feeds almost exclusively on common ragwort.
“Invasive non-native species of plants have usually arrived in the UK free from the creatures which munch on them and prevent them becoming dominant. As very few of our native herbivores are able to eat these plants they can become aggressive and drown out other native species of plants. Himalayan balsam, for example, has become so abundant along our watercourses that it has smothered most of the native plants and grasses. Unfortunately as Himalayan balsam dies back in the winter, it makes the now bare banks very vulnerable to erosion and damage.”
It is unlawful to allow the following harmful weeds, listed in the Weeds Act 1959, to spread onto agricultural land:
Spear Thistle (Cirsium vulgare)
This enticing plant is considered to be highly invasive and poses a significant threat to other native UK species. Spear thistle is a problematic weed because it produces a tap root on germination, with lateral roots that grow horizontally.
This plant is known to be very adaptable and has the potential to compete with almost every plant it encounters.
Common ragwort (Jacobaea vulgaris)
While the yellow flowers may look inviting, this “beauty” of a weed is actually poisonous to most mammals. It is one of the most commonly reported weeds found throughout the country, though its growth should be strictly controlled to protect livestock.
Broad-leaved dock (Rumex obtusifolius)
This green, leafy plant is highly invasive and will harbour several different types of unwanted garden pests. Broad-leaved dock can grow in all soil types, with “no climatic limitation” to stop this plant growing across the country.
Curled dock (Rumex crispus)
Known as a flexible weed, the curled dock plant will outcompete most native species. Curled dock and broad-leaved dock are both covered by the Weeds Act, 1959.
The other plants are listed in the Wildlife and Countryside Act 1981, explaining it is an offence to plant or grow the following:
Japanese knotweed (Reynoutria japonica)
This invasive plant can grow almost anywhere, causing significant issues to homeowners once it spreads throughout the garden. Japanese knotweed can take years to eradicate completely and can cost upwards of £10,000 to be professionally removed.
Common rhododendron (Rhododendron ponticum)
Though the small purple flowers may be deceptive, this widespread, tall plant is considered problematic for several reasons. Not only can it grow to a considerable height, but it will block sunlight for competing plants while doing so.
Eradication costs the UK millions every year, and is no easy feat to get rid of for good.
Himalayan Balsam (Impatiens glandulifera)
This intrusive species can be easily spread by animals, wind and rivers, making it hard to stop when it begins to grow. Around 800 seeds can be found on each plant, leaving plenty of opportunity for this ripe seed pods to shoot up to 22 feet away from its original site.
Giant hogweed (Heracleum mantegazzianum)
This uniquely shaped weed is filled with a powerful chemical known as furanocoumarins, which can cause significant injury when the sap touches human skin.
A burning sensation and permanent scarring makes this very dangerous to passers-by and is strictly controlled for this reason.
New Zealand pigmyweed (Crassula helmsii)
This invasive weed is known to kill any native species in its path, posing a considerable threat to your garden and surrounding land. Sales of this plant have been banned since 2014 in the UK in order to control the rapid spread.
If you happen to move into a new house and the plants were already there, you won’t face any action for simply having them. However, if you were to help it spread by planting it elsewhere, then you’d be liable for any consequences.