[4][5] Canfield's first credited performance on television was in March 1954 when she portrayed Frances in the episode "Native Dancer" on Goodyear Playhouse.

As Thelma Lou's "ugly" cousin in an episode of The Andy Griffith Show, she had an arranged blind date with Gomer Pyle, played by Jim Nabors.

The episode was originally scheduled to air on November 25, 1963, but it was preempted by the coverage of the assassination of President John F. Kennedy three days earlier.

Canfield was best known for her recurring role on the hit comedy series Green Acres as Ralph Monroe, the all-thumbs carpenter who greeted her fellow Hootervillians with her signature "Howdy Doody!"

[9] Canfield made her last public appearance in 2005 when she attended Eddie Albert's funeral with Green Acres co-stars Sid Melton and Frank Cady.