Managing Winter heliotrope

Winter heliotrope is one of winter’s problems for amenity weed management

One of Britain’s loved ornamental garden plants – Winter heliotrope (Petasites pyrenaicus) spreads fast! If allowed to grow in the wild it quickly becomes a problematic invasive weed, but the real issue is when it becomes a headache for local authorities as it takes over roadside verges and can be costly to get under control. Verges are where it loves to grow, and it does – rapidly. Growth is via its underground rhizomes, the hidden root system that’s not easily tackled. This is what makes it so difficult to control, as these roots have plenty of leaf buds which sprout plenty more new leaves.

Just like Japanese knotweed, Winter heliotrope is a non-native invasive species that was introduced to the UK from abroad. Winter heliotrope was brought over from the Americas and North Africa (mostly) to be planted in gardens during the 1800s as it provides good ground coverage and had a pleasant aroma. The problem came when gardeners started to thin the clumps out as it started to take over, and discarded the plant material into the wild. Little would they know how prolific this plant would become! And anyone who has tried to eradicate this plant will know what happens (like knotweed) if the smallest fragment of rhizome is left in the ground.

Which regions are being affected?

It’s beginning to show now, in late November, already seen popping it’s head up along many public highways by several of our surveyors, and reports coming in indicate that East and West Sussex are being particularly hit. Maybe the very wet late autumn weather has encouraged growth in this area of the country.

It must be good for something?

Well yes, it provides a colourful spread and its sweet (vanilla) smelling flowers which are produced during winter and early spring are a very important source of food for bees during the colder months. But, it must be controlled!