LONDON, ENGLAND - A 19-year-old actor from the Harry Potter films admitted Thursday growing cannabis at his mother's home, a crime which earned him the tabloid nickname "Harry Pothead."

James Waylett, who plays Potter-hating bully and fellow Hogwarts pupil Vincent Crabbe, was charged in April after being arrested with a friend, John Innis, 20, in central London.

On Thursday, he pleaded guilty to producing cannabis at a court hearing where it emerged that the pair were detained after Waylett took a photo of police while driving past a group of officers.

Innis's black Audi was stopped, and police found eight bags of cannabis and a knife. Officers subsequently searched the home of Waylett's mother in Kilburn, northwest London, and found 10 cannabis plants.

Another three bags of cannabis were found in Innis's possession. Innis admitted possessing a knife and having 11 bags of cannabis.

"Clearly the possession of cannabis is a serious matter and indeed the possession of knives is serious as well," said judge Timothy Workman at London's City of Westminster Magistrates Court, adjourning the hearing until next week.

Waylett appears as the overweight, greedy and dim-witted side-kick of villain Draco Malfoy in all of the films about boy wizard Harry.

The charge against him in April was announced just hours before the Potter stars walked up the red carpet in London for the world premiere of the sixth film, "Harry Potter and the Half-Blood Prince."

The tabloid Sun newspaper reported at the time that the the cannabis plants could have produced drugs worth 2,000 pounds (2,900 dollars, 2,200 euros), printing its story under the headline "Harry Pothead."