Iriya Asagao Matsuri, held from July 6 to 8 every year, is the largest festival in Japan dedicated to morning glories. The 120 producers and 100 fair stalls that line Iriya Kishimojin—meaning Iriya’s goddess of childbirth and children, and the common name for Shingen-ji Temple—and Kototoi-dori Street attract as many as 400,000 people during the three-day period each year.
The morning glories of Iriya are said to have gained fame around the late Edo period. The flowers were initially cultivated in Okachimachi, and as times changed they switched hands to producers in Iriya. By the mid Meiji period, the Iriya breeds were so attractive that they became popular as decorative plants.