On 30 August 2021, while the Craig-Browns were weeding their garden near Hamilton, Colin's hoe struck what he initially thought was a fungal growth or a sweet potato beneath the surface; he discarded these ideas after realising the object's size.
[5][6] At the suggestion of friends, the Craig-Browns submitted an application for the tuber, which was being kept in a freezer at the time, to Guinness World Records,[7] in the category of largest potato.
In March 2022, the Craig-Browns' application was declined after genetic testing conducted by Plant & Food Research confirmed that Doug was the "tuber of a type of gourd".
[8][9] Chris Claridge, who assisted in the genetic testing, suggested that the tuber may have grown as the result of infection or disease.
[10] Colin Craig-Brown had previously stated that he planned to turn Doug into vodka once the tuber's popularity died down.