The Spring Equinox, also referred to as the first day of spring, is a day that usually falls around March 20.
In the comic books, the Smurfs celebrate the Spring Equinox with a festival. In the story "The Jewel Smurfer", the Smurfs were busy making preparations for such a festival when Jokey was kidnapped while he and Brainy were looking for cattail stalks at the Ford Of The Merry Smurfer in the Smurf Forest. By the end of the story, the festival still took place.