If you've walked into a clothing store in the last couple of weeks, chances are that it looks like Coachella - or perhaps a band of hippies -- has taken over. The heart of "festival season", which unofficially kicked off in Austin during South by Southwest in March, begins Friday in Indio, California, when music and fashion fans alike flock to the desert for the first weekend of Coachella. As much as it's an event geared towards the music industry and its biggest enthusiasts, Coachella has become a hotbed for fashion marketing, and many of the biggest brands in the world bring their wares to the West Coast for a weekend (or two) of celebration.

This year, the likes of H&M (an official sponsor of the festival), Lacoste, Opening Ceremony, Old Navy and Aerie, as well as publications like Harper's Bazaar and Nylon, will be on location to host parties and pop-ups during Coachella. While the California event might be the most popular festival when it comes to branding opportunities, it's not alone: Between May and August, there is a music festival in the U.S. nearly every weekend -- from the Governors Ball in New York City to Lollapalooza in Chicago -- all of which are popular destinations for street style photographers and, in turn, an excuse for attendees to go shopping for new looks.

Coachella has ushered in its own in-between season of clothing, akin to resort or pre-fall. No less than 10 Coachella-centric lookbooks have landed in the Fashionista inbox over the last month, from retailers like NastyGal, LF, Urban Outfitters and bohemian clothing mecca Free People. In fact, many of these popular retailers seem to focus more on music festival culture in its first spring/summer deliveries than on actual runway trends. While seasonal runway looks are widely different year after year, "festival season" staples stay static, and have become mainstay pieces on shelves through much of early spring and summer.

Forever 21 releases an annual festival collection alongside its spring and summer lines. In 2013, it debuted a popular Coachella-focused campaign shot in Palm Springs starring Sky Ferreira. "Festival has become its own trend and season," says Linda Chang, general merchandising manager at Forever 21. She says the top sellers are headbands, boho tops and skirts, denim cut-offs, crop tops, fringed jackets and, of course, fun sunglasses. According to Chang, the collection isn't solely focused on Coachella, either: It's as fit for the Indio desert as it is for the dozens of festivals in Europe throughout the summer, like Roskilde in Denmark or Glastonbury in the UK.

California-based retailer Planet Blue is one of the West Coast's most well-known one stop shops when it comes to bohemian style staples, and while a free-spirited vibe is a huge part of the brand's DNA, it sees an uptick in sales of certain styles in the weeks leading up to Coachella."Festival season has legitimately become a fashion season, squished in perfect harmony between spring and summer," Planet Blue's fashion director, Jen Kassell, affirms. "Our deliveries 100 percent reflect what our customers are looking for, and this is exactly what they are looking for."

Fashion and music have always gone hand in hand, and bohemian style icons like Stevie Nicks and Penny Lane of "Almost Famous" are perennially popular. So, it makes sense that music festival culture has seeped into the fashion calendar, and it's likely here to stay. "I don't think 'bohemian' will ever be out of style - it's a way of life, less so than a trending fashion statement," Kassell says. "Music and art influence every aspect of the creative world. Fashion is a direct reflection of personal style, and a person's taste in music will likely reflect their own taste in apparel - it is entirely unique."

So, even if you don't have a music festival (or three) on your summer agenda, don't fret - you can still pick up a characteristically "Coachella" piece this season and look on-trend instead of out-of-place. But, do so with caution: You're always one flower crown away from looking like a major festival faux pas.

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