Guinness World Records have told Colin and Donna Craig-Brown that what they believed to be a potato is in fact a gourd tuber.
Guinness wrote to the pair to confirm scientific testing found their find was not a potato.
The discovery of the tuber happened last year when Mr Craig-Brown hit it with a hoe while gardening on their small farm near Hamilton.
He said it looks and tasted like a potato while admitting he did not know what gourd tuber tasted like.
"What can you say?" Mr Craig-Brown told the Associated Press.