In a field in the South Downs national park, undulating green hills meet the sky. In the distance, villages built of flint sit in the valleys, and chalky white cliffs lie like giant beached whales above the Channel.For decades, the field where I’m standing has been in an arable cycle. It was last sown for wheat in 2022, and this year would have been planted with barley.
Instead, it was sown with wildflowers: yarrow, vetches, clovers and oxeye daisies lie awaiting spring, when the monotonous green will break out into a sea of colour.
“We’re habitat banking,” says Ben Taylor, manager of Iford Estate farm near Lewes, in East Sussex. This farm is one of five in the country selected by government as a pilot project for the biodiversity net gain (BNG) scheme. Under the proposed rules (for England only at this stage), new roads, houses and other building projects must achieve a 10% net gain in biodiversity if nature is damaged on site: if a forest is bulldozed to make way for an apartment block, the developer must recreate a similar habitat, plus 10%. The priority is finding space for nature onsite, but if that is not possible, habitats are to be created elsewhere, ideally in the local area.
The scheme, expected to officially launch this month, would form England’s flagship nature market. This field and its latent quilt of wildflowers could be a sign of things to come, rolled out across the country.
“We’re selling out,” says Taylor. Most of the land in the surrounding 32 hectares (79 acres) – more than 40 football pitches – is now being managed for wildlife. This wildflower meadow is here to stay, because the agreement lasts for 30 years. “It’s basically in perpetuity,” says Taylor.
And this is just the start – ultimately, Taylor wants to turn two-thirds of the 3,000-hectare (7,400 acre) farm into BNG, which would generate 3,000 units. It should take a decade: Taylor has 20 developers working through the planning process. He currently has 221 units up for sale.
Each unit can be sold for between £25,000 and £30,000, fetching more than £75m for a 30-year period, excluding capital costs, costs of monitoring and lost income from farming.
But uncertainty looms. If launched as planned, BNG could transform thousands of hectares of English farmland, but the initiative has been dogged by delays, with some researchers concerned it could be scrapped altogether.
It’s a gamble selling up land on an emerging market, especially when it’s locked in for so long. “It’s crystal ball stuff,” Taylor says.
For some farmers, the scheme represents a chance to use and rehabilitate land that may have never been suited to farming in the first place. The most fertile land in the valley will still be used to grow crops, Taylor says, while less fertile areas will become wildflower meadows, wetlands and scrub for wildlife.
“It’s wrong that marginal land should be farmed as it is,” says Taylor. A lot of the local soils are thin, flinty and prone to erosion. During the second world war, “digging for victory” saw these grasslands grubbed up for farming. When peace came, food production was encouraged on every available patch, increasing yields by dousing the land in fertiliser, ripping out hedgerows and draining wetlands.
Another motivation for Taylor is that the climate crisis is making farming more uncertain. On the day I visit, 150 hectares (370 acres) of the valley floor is flooded. Taylor is fighting to keep these fields dry, pumping the water out – but under BNG, the land could become a floodplain grazing marsh.
“I’ve been here for 25 years and the change in weather has been phenomenal,” he says. “That has definitely pushed me in this direction.”
However, researchers from the universities of Kent and Oxford have raised concerns about delivery of the policy. Their study showed more than a quarter of BNG units are at risk of leading to no tangible increases in biodiversity.
Their main concern is onsite credits, which are within the boundary of a development site (Iford Estate’s are offsite), because there is no system in place for them to be properly checked. This means the habitats promised by developers might not be delivered. Sophus zu Ermgassen, an ecological economist from the University of Oxford, and author of the study, says: “If those promises of future habitats do not materialise, what is being facilitated by BNG is a considerable loss of green space. The success of this is really contingent on those promises from developers materialising.”
Researchers are calling for them to be tracked more closely, with spot checks from government officials or satellite tracking, although neither of these are part of the current policy. “It is too early to say if BNG will help stop wildlife loss in the UK. As it stands, net gain will probably not deliver for wildlife,” says Zu Ermgassen.
There is also concern from the scientists that the legislation could be derailed entirely, after a recent effort by government to scrap river pollution rules for housebuilders. The nutrient neutrality scheme aimed to save England’s rivers from being overloaded with nitrates and phosphates by allowing developers to pay for “credits” to improve local wetland areas. Currently the scheme remains in place – but Zu Ermgassen says the clashes over it show how biodiversity measures could be vulnerable.
Despite the uncertainty, many developers are stocking up on credits in anticipation of the legislation. “We’re pretty confident it’s going to happen – people are good to go,” says Dan James, development director of the Eden Project in Cornwall, which has created a new company – the Eden Project Wildflower Bank – that will create flower-rich habitats using BNG units. “We’re just going to go for it,” he says.
Since 2017, his team has made 50 hectares (123 acres) of wildflower habitats. The aim is to start sowing meadows in March or April, and create 1,000 hectares (2,471 acres) of wildflower habitat over the next decade. Already, James has 100 hectares lined up for year one. “The legislation gives us the opportunity to monetise that programme a bit more, and expand our current capacity,” he says.
Taylor remains confident BNG will go ahead. Even if the scheme is scrapped, he believes many developers will stick around, because lots of local plans require biodiversity gains independently of central government. The UK has lost 97% of its wildflower meadows since the 1930s and BNG could be a small part of undoing that process and restoring nature on farms. “I see it as coming full circle,” says Taylor.
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