Warning to avoid toxic Giant hogweed

Giant hogweed is an invasive weed that can cause injury in summer due to its extremely toxic sap.

The warning comes from the Property Care Association, which emphasised that the plant is a danger to public health.

With two concurrent wet springs this year and in 2023, experts at the PCA say weather patterns are creating an opportunity for the plant to thrive and gain ground across the country.

Contact with any part of Giant hogweed, followed by exposure to UV light - including the sun - can cause severe discomfort and blistering to the skin.

Daniel Docking, technical manager of the PCA’s invasive weed control group, said that raising awareness of its presence, and its health implications, are key to creating a safer environment.

He said: “Children are particularly vulnerable, as they can encounter the plant while playing outdoors. Anyone unfortunate to come into contact with Giant hogweed can develop symptoms including a rash, itching and blisters where skin touches any part of the plant.

“In some cases, people need urgent medical attention because the blistering can be so severe. There can be longer-term complications too, as the condition can reoccur over a period of years, with the rash and the itching coming back every time the skin exposed to UV light.”

Further details about Giant hogweed and how to control it can be found at www.property-care.org.

The plant’s standout is its size, as it grows up to five metres high and has a stem that measures up to 10 centimetres in diameter.

Flowers - The plant produces a large, white, umbrella shaped flowering head, with a single umbel capable of producing 50,000 seeds per head.

Leaves - Giant hogweed has sharply serrated or divided leaves, which reach up to three metres.

Markings - Giant hogweed’s stem is usually covered in blotchy purple markings. Sharp bristles can also be found on the stem and under the leaves.

Daniel added: “Giant hogweed has distinctive features, which should help people to recognise it, although we urge the public not to get too close to the plant to identify it.

“The plant can sometimes be confused with UK’s native Hogweed, Cow Parsley or even Hemlock, all of which are much smaller in size and have leaves with a smoother outline.”

The PCA provides a means of identifying specialist contractors and consultants with the expertise to control and manage invasive species such as Giant hogweed, as well as other invasive, non-native plants including Japanese Knotweed.

A full list of companies in the Invasive Weed Control Group is available in the ‘Find A Specialist’ section on the PCA website and more details on invasive weeds in general are available via www.property-care.org/homeowners/invasive-weed-control

Part of the PCA’s Invasive Weed Control Group’s remit is the development of best practice standards and collaboration with other professionals, including surveyors, ecologists, local authorities and government departments to build a safer environment for all.