From Muppet Wiki

A group of Flowers appeared in episode 401 of The Muppet Show, and sang "Good Day Sunshine" in episode 522. Similar flowers make up part of the chorus of "Zip-a-Dee-Doo-Dah" in episode 420. One of them appeared in Mopatop's Shop as Grace the Delphinium.

They also appeared amongst a much laregr variety of other flowers in Julie Andrews: One Step Into Spring for the number, "Hurry, It's Lovely Up Here."

Other flowers and shrubbery could later be seen in "Take the First Step" from The Adventures of Elmo in Grouchland, as well as Stuckweed.