Transport for London (TfL) says it has doubled the size of wildflower verges across its road network in just two years, expanding them to more than 520,000 square metres — roughly 100 Trafalgar Squares — as part of efforts to boost biodiversity and make London more resilient to climate change.

TfL first began experimenting with wildflower verges in 2019 through pilot schemes alongside the A40 in Hillingdon and the A406 in Redbridge. The approach involves reducing mowing from up to eight cuts a year to just two, removing grass cuttings, allowing wildflowers to establish, and creating richer habitats for insects and other wildlife.

The verges provide nectar, food and shelter for a range of species, including bees, butterflies, birds and small mammals. They also help capture carbon dioxide in the soil and reduce emissions by cutting the frequency of maintenance visits.

New wildflower verges have been established at several locations over the past year, including 5,000 square metres along the A10 in Enfield, 2,000 square metres on the A2 in Bexley and 1,700 square metres beside the A217 in Sutton. TfL has also planted wildflower seeds donated by Butterfly Conservation on traffic islands near Rotherhithe roundabout, replacing more formal planting schemes.

The new sites add to an expanding network of wildflower verges across London, including publicly accessible areas at Redbridge Roundabout and alongside the A40 in Hillingdon, where residents can experience the habitats firsthand.

Monitoring carried out with the charity Butterfly Conservation suggests the programme is already benefiting wildlife. Since 2023, surveys have tracked butterfly populations across the verges, and in 2025, volunteers carried out 118 surveys at 34 sites. These recorded around 720 butterflies from 22 different species, along with about 100 day-flying moths.

Butterfly sightings were, on average, more than 50% higher than in the previous year.

Deputy Mayor for Environment and Energy Mete Coban said the expansion demonstrated how relatively simple changes could make a significant difference for nature.

He said: “The expansion of wildflower verges across London shows how simple changes can have a big impact, helping nature thrive.

“Alongside these verges, we have planted more than 640,000 trees, including two major new woodlands, and created or restored over 2,000 football pitches worth of green space.”

The wildflower programme forms part of TfL’s wider environmental strategy, which also includes measures to reduce pollution entering waterways and lower flood risk.

Working with City Hall and other partners, TfL has delivered almost 50,000 square metres of Sustainable Drainage Systems (SuDS) across London, including nearly 18,000 square metres in the last financial year. These schemes use features such as rain gardens, planted roofs and wetlands to slow the flow of rainwater into drains and rivers.

TfL added that it plans to install a further 10,000 square metres of SuDS over the next year, including as part of the A23 Streatham Hill improvements, which aim to make walking and cycling safer and more attractive.

Before land is converted into a wildflower verge, TfL assesses factors including the suitability of existing vegetation, maintenance access requirements, proximity to homes and any potential impact on road safety.