The man had filled a 200-litre hot water tank with gas in order to shoot kohlrabi, also known as German turnip, in his garden.
As the man, who is in his 50s, attempted to launch a kohlrabi, the tank exploded.
According to Ann Line Finanger of the police in Helgeland, northern Norway, the man was thrown up in the air by the blast and then landed on his arm, causing a mild fracture.
”He was taken to the hospital for a check up. There was no serious injury,” Finanger told the local Rana Blad newspaper. ”The case will be investigated further by police.”
The injured man was released from hospital on Sunday.
Eyewitnesses told Norway's VG newspaper that the accident happened as part of a birthday celebration when a number of people decided to use the kohlrabi cannon.
Although the kohlrabi resembles a turnip, it is more closely related to kale and cabbage. In Norway, the vegetable is a staple of Christmas dinner alongside pinnekjøtt, steamed lamb ribs that have been salted and dried.
It is unclear why the man decided to build a kohlrabi cannon, although in the Super Mario Brothers spinoff Captain Toad: Treasure Tracker, players can fire turnips at their enemies.