Growing this species of hogweed could land you with a heavy fine in France
Homeowners are banned from planting or keeping this invasive species in France
Sosnowski hogweed can grow up to 3–3.5 metres tall, forming large umbrella-shaped white flower heads and producing thousands of seeds per plant.
Tomas Ragina/Shutterstock.
Growing, selling or introducing certain exotic plants in France can land home owners in serious legal trouble.
One of the most striking examples is Sosnowski’s hogweed, a large flowering plant which although impressive in appearance, is tightly regulated across France and the EU.
Native to the Caucasus region, the hogweed grows to epic proportions, reaching between 3–3.5 metres tall in certain parts of Europe.
The hogweed was introduced in the former Soviet Union as a potential crop to feed livestock before becoming notorious for its invasive nature and health risks.
Scientists back then were looking for a fast-growing, high-yield crop that could be used to feed cattle. Soviet botanist Ida Panovna Mandenova first described the hogweed subspecies, naming it in honor of her professor.
However, its aggressive growth and reproductive capacity quickly became a problem for the Soviets. Each plant can produce thousands of seeds, and once established outside controlled environments, it spreads rapidly into the wild.
The plant’s status in France today
The plant is now treated as a high-risk invasive alien species and is covered by national and European regulations on prevention and control.
In France, Sosnowski’s hogweed has been banned since 2018 under rules aimed at preventing the spread of invasive alien species. It is illegal to sell, transport, cultivate, possess or deliberately introduce it into the natural environment.
In practice, this means it should not be found in garden centres or intentionally planted in private gardens.
Although not considered established in France, the species is monitored because of its invasive behaviour in other European countries. If found, this is usually along riverbanks, roadsides and other wasteland.
Why is it banned in France?
There are around 70 known species of hogweed in the world, many of them harmful to human health and the environment. Sosnowski’s hogweed is considered one of the worst.
It spreads quickly and can form dense colonies that crowd out native plants. The CDR-EEE, (the French Invasive Alien Species Resource Centre) says its large leaves can capture up to 80% of available sunlight, preventing other plants from growing and reducing biodiversity. Over time, this can also weaken soil stability.
The plant's sap also contains toxic substances called furanocoumarins. If sap gets on the skin and is then exposed to sunlight, it can cause severe burns, blisters and painful skin reactions that may take weeks to heal.
Gardeners are strongly advised not to handle the plant directly. Cutting, pulling or mowing it without proper protection can increase exposure to its toxic sap. Suspected sightings should be reported to local environmental authorities or municipal services, which are trained to manage invasive species safely.
Because of its classification under French and EU invasive species law, deliberately planting or keeping this species is illegal.
Homeowners who fail to comply risk severe penalties under the Environmental Code, including fines of up to €150,000 and up to three years of prison, particularly if the plant is introduced intentionally or allowed to spread into the natural environment.
