A set of animation cells which sold on eBay in 2017 showed that the opening credits were originally supposed to end with Junior chomping on a portion of the show's title. He then bites into the right side of the screen and stretches it to the left until the entire screen goes black. As it was broadcast, the sequence faded out before any of this occurred.
In several different shows, there are fleeting glimpses of a character clad in dark sunglasses which bears an uncanny resemblance to Jack Nicholson, who had a small but memorable role in The Little Shop of Horrors (1960).
Mel Welles, who played Mr. Mushnick in the 1960 film, wanted to reprise his role in the animated series, but due to studio logistics, all of the vocals were recorded in Canada.
Roger Corman, who co-wrote and directed The Little Shop of Horrors (1960) (which this series was loosely based on), was a creative consultant on the show.
A longstanding internet rumor is the show was conceived by Frank Oz, director of the 1986 movie-musical, but there's no evidence to support this claim. It's more likely that it was conceived by Roger Corman, who produced the show and directed the original 1960s film.