The biggest event of the year in Sierra Madre is always this festival to celebrate the Guiness Book of World Records‘ honoree for world’s largest blossoming plant. The downtown Sierra Madre area comes alive with a free street festival, promising all the wonderful food, music, and craft stalls that a good street fest ought to have.The star of the show, of course, is the epic flowering wisteria vine, which has been delighting the area with blooms for more than a century.And if you’re wondering about the spelling of the word “wistaria” versus “wisteria,” the simple answer is that this 120-year-old plant has lived so long that it outlived the spelling of its name; wistaria was the 19th century spelling.