The field was planted as the backdrop to a commemoration performance from Wildworks Theatre, and is set to bloom each summer until 2018.
Heligan is recognised by the Imperial War Museum as a living memorial to the ‘Gardeners of Heligan House’, many of whom died in the Great War.
Iain Davies, Heligan gardens and estate manager, said: "In 2014 the ground on West Lawn was ploughed and harrowed by heavy horses using century old practices. The resulting poppy display although stunning was slightly hindered by last year’s incredibly hot summer.
"This year, the ground was left for the poppies to re-seed naturally which has resulted in an incredibly prolific poppy explosion. The effect is simply breath-taking. To describe the field as a sea of red simply doesn’t do it justice, you need to experience it for yourself. To simply walk through the poppies is incredibly beautiful and uplifting."