High-ranking civil servant Kevin McGurgan is in Afghanistan helping run the ground-breaking Wheat for Poppy scheme among 32,000 farmers.
The British Government-funded programme aims to persuade farmers to grow wheat instead of opium-producing poppies, the main source of Taliban income.
About 90 per cent of the world's opium comes from Afghanistan, of which 80 per cent comes from Helmand, meaning the region is responsible for two thirds of the world's heroin supply.
Helmand is also the scene of Afghanistan's most violent insurgency. The Taliban force farmers to grow poppies and where their income is under threat there has been fierce fighting.
But where production has been removed, such as in the northern Nanghar area near Kabul, the Taliban have left.
Mr McGurgan, aged 37, is a former Devonport High School for Boys student.
Now a member of the Foreign and Commonwealth Office (FCO) and the Provincial Stabilisation Team (PST) in Afghanistan, he is also deputy head of mission for Helmand.
He said Wheat for Poppy gives families an alternative crop to grow and one which is fetching rising prices.
"There's no doubt the Taliban are unnerved by it and in some places have told people not to do it," he said. "It does provide a grass roots challenge to the Taliban's authority."
The programme began last year and a successful harvest next month will determine whether it continues.
"I'm confident that if we get it right this year we should be building on it," Mr McGurgan said. "We need to think about this in a campaign sense like the military. We should keep rolling it out and it will keep destabilising the Taliban."
Poppies are easy to grow in Afghanistan's dry landscape, and fetched good prices until recently when the international price of opium plummeted, making it uneconomical for many farms.
Eradication programmes have only had limited success due to corruption. It is thought 103,000 hectares of poppies are grown in Helmand, but last year only between 2,500 and 8,000 hectares were actually burned.
The PST has 119 staff in Helmand, at five sites. Mr McGurgan said they are working with Afghans to provide security and 'good governance' creating such things as community councils to help solve problems and disputes.
Britain is ploughing £59.5million into the country this financial year for projects such as new schools and roads.
"These are straitened times and it's a big political question which gets you back to the reason we are here in Afghanistan in the first place," Mr McGurgan said.
He said it is to prevent Afghanistan from becoming a base for a '9/11-style attack' and so, in the long term, the country can 'stand up on its own'.