In Pagan Rome, Floralia was celebrated April 27th to May 6th, or April 28th to May 2nd, according to some sources. This was the festival of the Goddess Flora or Chloris and the flowering of Springtime. Ovid indicates it was instituted in Rome in 238 B.C., at the command of an oracle in the Sibylline Books. It appears it was a celebration made to appeal to the Goddesses for protection of the flowers. (Also most likely flowering plants that resulted in fruits)

This festival was primarily one of flowers, but had definite sexual overtones in the larger cities, though more rural towns probably kept it simple and less licentious. Offerings were made to Bona Dea , the Lares (household guardian spirits), and Maia during this time. Roman writer, Gaius Valerius Maximus wrote that theatrics made up a major part of the various amusements, and that it was customary for the crowd to yell for the female actors to appear nude on stage, the better to amuse the masses with their indecent gestures and dances. It was also celebrated with lewd games, strip teases, scattering of peas and lentils, and letting loose hares and goats in the streets(both considered particularly randy animals by Romans). A good many of our modern Beltane customs appear to derive from this festival. (Can we say Easter Bunny?)

Sources

• http://www.ku.edu/history/index/europe/ancient_rome/E/Roman/Texts/secondary/SMIGRA*/Floralia.html
  
• Parts taken from an article I did in 1999, for Full Circle, a now defunct pagan magazine distributed in Northern Florida. Sources long since lost, sorry