Cast notes
The only actors who appeared in all seven seasons were Edgar Buchanan, Linda Kaye Henning, and Frank Cady. Buchanan was the only one to appear in every episode. Linda Kaye Henning appeared in all but two episodes: "Bobbie Jo and the Beatnik" (Season 1); and "Have Library, Will Travel" (Season 2). Edgar Buchanan, who portrayed Bea Benaderet's character's uncle, was only three years older than Benaderet in real life.
Veteran character actor Charles Lane played Cannonball nemesis Homer Bedloe in 24 episodes. Lane said that he perfected his stern curmudgeon character-type on I Love Lucy. Recalling in 1981 his many roles, he said "They were all good parts, but they were jerks. If you have a type established, though, and you're any good, it can mean considerable work for you." The New York Times reported that Lane's persona was so familiar to the public, "that people would come up to him in the street and greet him, because they thought they knew him from their hometowns."
In the first-season episode #32 "Dog Days At Shady Rest", Higgins, the actor dog, was featured as "Sheba", the dog of Betty Jo's boyfriend Orville Miggs (played by actor Jimmy Hawkins). That episode gave the producers an idea. It was decided at the start of the 1964–1965 season to add a new character to The Shady Rest - a dog. As a result, Higgins became a regular cast member. His first appearance was in the second season opener "Betty Jo's Dog". In that installment, coming home on the first day of school, Betty Jo meets a little male dog who immediately attaches himself to her and the Bradley family. Kate, at first, is against keeping him but by the end of the episode, she is won over by him and allows him to stay. Also, in that episode, the subject of Higgins's name is addressed. At first, different names are suggested by the sisters when he first arrives ("Spike", "Prince", and "Byron"), but they never decide, so the dog at that time is not actually named. Eventually, the character's name becomes simply "Dog" or "Boy". Press releases for the show referred to him as the "Shady Rest Dog". (The fifth-season episode "Higgins, Come Home" (broadcast January 27, 1968) refers to the dog's real name, but the title itself is not displayed on the episode.) Higgins remained with the show until its cancellation in 1970. During that time, he won a PATSY Award, and he also was cover-featured on an issue of TV Guide. Higgins had a close rapport with Edgar Buchanan. In the official cast pictures taken each year during the run of Petticoat Junction, Buchanan is shown holding or petting the dog. Higgins went on to star in the successful 1974 film Benji which also featured Buchanan in a cameo role. Linda Kaye Henning indicated in a TV interview her father, the show's producer, had planned to run a contest to name the dog but that never materialized and thus the dog was left without a "proper" name.
Another new character was introduced for the 1964–65 season to serve as a female nemesis for Kate Bradley - Selma Plout. Virginia Sale briefly reprised her role in the first season of Green Acres (her character is not mentioned by name, but is listed in the end credits). During the third season, Elvia Allman (who had appeared in season one as Gladys Stroud) was brought on as Cora Watson for one episode (a role she reprised on Green Acres the same season). Starting with Season 3 (1965–1966), Sale's Selma was replaced by Allman. She appeared in 19 episodes in all, which extended to the end of season 7 (1969–1970). Selma's daughter Henrietta Plout (first played by Susan Walther in season 3 then by Lynette Winter) was introduced at the same time and appeared in seven episodes over the next three seasons. Selma tries repeatedly to marry off the seemingly homely girl, the butt of many "plain Jane" jokes. In her next-to-last episode, the Bradley sisters give Henrietta a glamorous makeover and she is revealed to be quite attractive.
Mike Minor first appeared on the series as Selma Plout's son Dan in the second-season episode "Mother Of The Bride" that aired December 15, 1964. After that episode, the character of Dan Plout is never seen again. Two years later, in the fall of 1966, Mike Minor rejoined the series as handsome crop duster Steve Elliott. Steve is originally the love interest of eldest daughter Billie Jo, but later marries (youngest daughter) Betty Jo.
The three Bradley sisters (played by Linda Kaye Henning, Pat Woodell, and Jeannine Riley) form a Beatlesque band called "The Ladybugs" with their friend Sally Ragsdale (Sheila James) in the season-one episode "The Ladybugs". They wear mop-top wigs and perform the Beatles song "I Saw Her Standing There" with the word "Him" substituted for "Her". On March 22, 1964, mere days before this episode aired, the four actresses performed this same song as "The Ladybugs" on The Ed Sullivan Show. Ed invited his viewers to tune in later that week to see the girls on their show.
Frank Cady, who played Sam Drucker, was the only actor in television history to play the same recurring character on three different shows at the same time. He was a regular on Petticoat Junction and Green Acres, in addition to some late series guest appearances on The Beverly Hillbillies.
Benaderet had played Mrs. Granby on the short-lived 1950 radio show Granby's Green Acres. This show was the inspiration for the Petticoat Junction spin-off Green Acres. The Mrs. Granby character was altered on television and became Lisa Douglas, played by Eva Gabor. Jack Bannon, Benaderet's son, played small parts over the course of the show, usually as a boyfriend or date for one of the Bradley girls. Byron Foulger played two different recurring characters on Petticoat Junction. In the early seasons, he was banker Mr. Guerney, and in later seasons, he was train engineer Wendell Gibbs. Jimmy Hawkins appeared in five episodes as Betty Jo's love interest Orville Miggs.
In season seven, Steve and Betty Jo's baby Kathy Jo was played by Elna Danelle Hubbell. In season six, Kathy Jo was played (uncredited) by infant twins Heather and Barbara Whiter. Heather said her sister and she landed the role when their mother heard that the producers were looking for red-haired babies. She also said that she has no first-hand memories of working on the show.