Tourists view peony flowers during the 37th China Luoyang Peony Cultural Festival in Luoyang, central China's Henan Province, April 1, 2019. The 37th China Luoyang Peony Cultural Festival was launched Monday at the China National Flower Garden in Luoyang. During the festival, peony species under artificial flowering time regulation have reached their full blooming, while other species left to flower naturally have also begun to bloom. (Xinhua/Li Jianan)