On April 1st, 1957 the Panorama on the BBC broadcasted an episode talking about what a good year it had been for the spaghetti harvest due to the mild winter and the disappearance of the spaghetti weevil. The program showed images of family pulling spaghetti of trees and putting it in baskets and assured viewers that there was nothing better than home-grown spaghetti.
Viewers did not realize that it was a hoax and hundreds of viewers called the BBC asking where they could get a spaghetti tree. The BBC told callers to Place a sprig of spaghetti in a tin of tomato sauce and hope for the best.
The Panorama show inspired San Giorgio Spaghetti to spoof it in their TV ad.
(Thanks MM and BW)