Charlie Hamilton-James said: "I am a huge fan of Heligan for its leading approach to nature and the environment. It has inspired us for 20 years."
The show is for the BBC2 Natural World programme, said Hamilton-James, who stars in BBC's Halcyon River Diaries with his wife, Philippa Forrester.
Cameras follow a family's year living by a west country river. The couple are also using the Lost Gardens of Heligan in St Austell, Cornwall, as a venue for signing books accompanying the Halcyon River Diaries.