Work to create rich meadows and grasslands along a five-mile stretch of the Durham coast will begin this year.
The National Trust is creating 50 hectares of wild flower meadows between Hawthorn Dene and Cotsford Field in Horden.
The charity says the ambitions plans will benefit a variety of plants, birds and insects.
Eric Wilton, general manager for the National Trust South of Tyne property group, said: "This special area features some extremely rare magnesian limestone habitat.
"It’s the only place in the world where you find this geology on the coast, which in turn leads to an unusually diverse range of wild flowers and insect life.
“Some meadows are home to up to 50 species of plant life in a square metre and we want to extend these areas. Lots of local residents and visitors who already enjoy the coast will be able to see improvements over the coming years – it’s very exciting.
The £40,000 project has been made possible by players of the People's Postcode Lottery, which awarded the Trust £750,000.
“The support from players of People’s Postcode Lottery is a huge boost to nature conservation on the Durham Coast," he said.
""Meadows will become healthier and more wildlife rich, views of this fantastic coastline will become even more beautiful. We’re proud to be leading on this project; our rangers and volunteers can’t wait to get started on the work.”
Work will focus on the removal of species such as bracken and Himalayan balsam, which the Trust says are out-competing native species in some areas, followed by the management and improvement of grassland through a programme of cattle grazing and grass cutting.
Cattle grazing encourages wild flower growth as cattle crop the grass and turn over the soil, creating good growing conditions for meadow flowers such as wild thyme, bird’s-foot trefoil, bloody cranesbill and common rock-rose, the larval plant of the rare Durham Argus butterfly.
Areas fenced off for grazing will also reduce disturbance to ground-nesting birds including skylark, lapwing and grey partridge.
As well as helping to restore meadows on the Durham coast, the £750,000 People’s Postcode Lottery award will be used to fund several other National Trust conservation projects around the country, along with continuing support for Heritage Open Days.
Clara Govier, head of charities at People’s Postcode Lottery, said: “We are thrilled that funding from players of People’s Postcode Lottery to the National Trust has increased in 2018, supporting the charity’s nature programme for the first time, alongside continued support for Heritage Open Days.
"We are delighted to see players’ funding supporting significant conservation activity across England and Wales to improve a range of priority habitats, from coastal slopes and chalk grasslands, to woodland pasture, and to safeguard species that call these places home.”
Matthew Oates, a National Trust nature expert, said: “We are determined to ensure our countryside is healthy and beautiful for the next generation.
"The support we have from players of People’s Postcode Lottery for nature conservation, alongside continued support for Heritage Open Days, is a wonderful boost to our work in 2018.”