Stephen Richardson grew up on Grange Farm in Ashwellthorpe, but spent 25 years growing grapes and making wine in the renowned Paarl region, near Cape Town.

The 67-year-old returned to his Norfolk farm in 2021 and sold the vineyard – seeking to focus on a single business, to limit his risk and spend more time closer to his family in “semi-retirement”.

But amid a changing climate, volatile arable returns and dwindling EU-era subsidies, he wanted to restructure the farm and safeguard its future income.

So he has embarked on an ambitious project to transform 55 acres of marginal land into a mosaic of wildlife habitats, in a long-term plan to generate revenue under new Biodiversity Net Gain (BNG) rules.

Norfolk farmer Stephen Richardson is working with Environment Bank on a fen habitat restoration project on his land near Wymondham (Image: Sonya Duncan)

The Wymondham Habitat Bank is part of a rapidly-growing national network established in partnership with BNG provider Environment Bank – creating nature recovery sites on low-yielding farmland while selling biodiversity units to developers seeking to offset their own ecological footprint.

Developers are now required to replace habitats and biodiversity lost during building projects – plus a net gain of at least 10pc – either by ringfencing wildlife areas on site, or by paying other landowners to create equivalent off-site BNG units for them nearby.

Mr Richardson hopes to use these 30-year agreements to fund his project, which aims to recreate rare fen habitats, replant native trees and reconnect fragmented wildlife hotspots in the River Tas valley.

“When I came back from South Africa in 2021, I was looking at how I could restructure everything – and this term ‘natural capital’ kept springing up,” he said. “Now everyone’s talking about it.

Norfolk farmer Stephen Richardson and Environment Bank senior ecologist Eleanor Walker at the site of the fen habitat restoration project near Wymondham (Image: Sonya Duncan)

“This is marginal land which didn’t always consistently grow standard crops. But this [BNG] brings a more guaranteed income. Obviously it’s a leap in a very different direction, but one I’m being well supported with.

“I partnered with Environment Bank two years ago.  We’re creating a variety of habitats according to the soil type. We’re creating a fen habitat down the bottom with ponds and scrapes. A lot of it will be lowland grassland, but there will be mixed scrub, some orchard planting, some hedge planting, tree planting, and then we will introduce a few cattle on here, to help promote wildflowers.”

The project includes replanting black poplar, one of Britain’s rarest native trees, and the restoration of a previously in-filled “ghost pond” which has been carefully excavated after being identified beneath the field through old maps and aerial photography.

Environment Bank senior ecologist Eleanor Walker at the site of the fen habitat restoration project near Wymondham (Image: Sonya Duncan)

Eleanor Walker, senior ecologist for Environment Bank, said the scheme has the potential to encourage rare wildlife species to a valuable habitat.

“Norfolk in itself hosts 85pc of the world’s fen habitat, and fen habitats are highly sensitive,” she said. “You require a high water table, and you need base rich, calcareous soils – and those attributes of a fen are really hard to find.

“We are very lucky here, in that we’ve got areas like Flordon Common SSSI down the road, and there’s a priority habitat fen next door, all of which will lend species to this site.

“Hopefully, we’ll see things come back like the swallowtail butterfly, which is a real key driver of Norfolk species, and other things like the common darter dragonfly, the Desmoulin’s whorl snail, which is a really rare species of snail that has the potential to come back, as well as larger species like marsh harriers. We’ve got tawny owls and woodcock on site, and in terms of vegetation, there’s marsh marigold here and flag iris and meadowsweet.”

Norfolk farmer Stephen Richardson is working with Environment Bank on a fen habitat restoration project on his land near Wymondham (Image: Sonya Duncan)

She said BNG is a “win-win” – bringing significant ecological benefits, while generating new revenues for landowners by leveraging private investment rather than public funding.

“The key message we’re trying to drive home with BNG is to demonstrate the success of it and how it can work mutually for our nature and for our landowners as well,” she added.

Although the three-year restoration is about halfway to completion, the site is already generating revenue – selling about 65pc of the 120 biodiversity units created so far.

Norfolk farmer Stephen Richardson is working with Environment Bank on a fen habitat restoration project on his land near Wymondham (Image: Sonya Duncan)

Mr Richardson said: “Obviously there will be a profit share, but the lease and the management fee start from the word go, so there is already income from my perspective, and Environment Bank are covering most of the capital costs.

“I think I’ve been quite used to taking risks. I think buying a vineyard and developing a winery in South Africa is a fair risk.

“But this is a 30-year arrangement so whatever happens in the future there is a safeguard there.”

He said he remains committed to producing food on his 200-acre farm, where most of the work is contracted by “a very close friend, who farms up the road”.