Prince, who headlines the Essence Festival’s main stage in the Mercedes-Benz Superdome Friday, July 4, has requested that everyone wear purple, his signature color, to the show, the festival announced Wednesday.

Prince’s classic album, “Purple Rain,” was released 30 years ago on June 25, 1984. The album’s worldwide sales exceed 20 million copies. Featuring the hit singles “When Doves Cry” and “Let’s Go Crazy,” “Purple Rain” was added to the Library of Congress’s National Recording Registry in 2012.

The Essence Festival, running Thursday through Sunday at the Superdome and Marc N. Morial Convention Center, celebrates its 20th anniversary this year. Prince previously performed at the festival in 2004.