In recent years, a movement known as “No Mow May” has gained traction in parts of the UK, encouraging individuals, councils, and organisations to pause mowing during the month of May to benefit urban biodiversity. The campaign, which began in 2019 through the efforts of the conservation group Plantlife, aims to provide early spring pollinators such as bees with vital food sources found in daisy, buttercup, dandelion, and other wildflowers that flourish when grass is left uncut.

The idea has been embraced by numerous UK local authorities, including the London borough of Lambeth and 54 other councils, as well as some communities in the United States. It encourages letting council-managed green spaces grow wild during May. Local residents have observed the effects, with wildflowers like red clover carpeting green areas in some urban settings. However, once May ends, many councils resume mowing, as was the case in Lambeth, raising questions about the lasting impact of the initiative.

Critics of No Mow May point to limited evidence supporting sustained biodiversity benefits beyond the initial growth period. Some may also cite financial implications; for example, Warwick District Council reported a £29,000 budget overspend associated with the heavier grass cutting required after a month of longer growth. Additionally, a 2020 American study previously used to support No Mow May was found to contain significant errors, causing major media outlets such as the New York Times to retract related stories. Debate continues surrounding the campaign’s claims regarding carbon reduction and cost savings.

Despite these concerns, numerous reports highlight a sharp decline in the UK’s flying insect populations, with a Buglife and wildlife trust study in 2021 noting a decrease of up to 60% over two decades. Urbanisation is cited as a key factor contributing to this decline in the 2019 State of Nature Report. Groups like Nature 2030 stress the potential of the UK’s 85,000 hectares of publicly accessible green spaces to serve as interconnected wildlife corridors, aiding pollinator recovery efforts. The Wildlife Trust has noted that pollinators contribute to the productivity of UK crops valued at around £690 million annually.

Surprisingly, public grass verges cover approximately 1.2% of UK land. An ecological newsletter, Inkcap, published a 2021 report on verge cutting, revealing unintended consequences of changing mowing practices. Reduced mowing frequencies, sometimes adopted for budget reasons—as seen in Sheffield—require different grass clipping management, which can affect soil nutrient levels. Wildflowers tend to thrive in poorer soils, and road verges now host nearly half of the UK’s wildflower species, including rare varieties such as harebell, tower mustard, spiked rampion, and multiple types of orchids. These rich habitats provide abundant nectar for millions of pollinators.

Frequent mowing has been shown to negatively impact biodiversity while presenting financial challenges. Tower Hamlets, one of London’s less affluent boroughs, reportedly spends £10,000 annually on mowing just 0.12 miles of grass verge every fortnight over six months, costing around £52 per square metre.

Despite the mixed evidence, No Mow May continues to expand. According to Plantlife’s Mark Schofield, 56 UK councils have registered to participate in 2024. Some councils claim longer-term cost savings and ecological benefits; Dorset council reports a reduction in mowing expenses by nearly half after seven years of involvement. Schofield explained that the primary goal of the initiative is to “depart from tradition and manage areas so they flower and provide shelter for wildlife throughout the summer.” He also emphasised the potential of utilising margins of publicly owned football pitches, which currently are typically fully mown, saying that creating 10-metre unmown margins around pitches could create significant wildlife habitats equivalent in size to 100 football pitches per county.

Visitors to these spaces, such as families in London, have been prompted to reconsider aesthetic expectations of urban greenery. Rather than viewing uncut lawns as neglected or untidy, advocates encourage seeing them as vibrant habitats supporting an array of wildlife. This shift in perspective aligns with the thoughts of American writer Michael Pollan, who described conventional mowing as “nature purged of sex and death.”

Some areas are further extending the duration of growth pauses beyond May. For instance, Ealing Council has initiated a “Let It Bloom June” campaign, signalling a continuing evolution of urban ecological management strategies.

The Financial Times is reporting these developments as part of the broader emerging conversation around urban biodiversity and green space management.

Source: Noah Wire Services