A tourist takes photos of peony flowers at a garden in Xi'an, capital of northwest China's Shaanxi Province, April 12, 2014. (Xinhua/Liang Aiping) 

Tourists take photos at a garden with peony flowers in Xi'an, capital of northwest China's Shaanxi Province, April 12, 2014. (Xinhua/Liang Aiping) 

A tourist takes photos of peony flowers at a garden in Xi'an, capital of northwest China's Shaanxi Province, April 12, 2014. (Xinhua/Liang Aiping) 

Tourists visit a garden of peony flowers in Xi'an, capital of northwest China's Shaanxi Province, April 12, 2014. (Xinhua/Liang Aiping) 

Tourists visit a garden of peony flowers in Xi'an, capital of northwest China's Shaanxi Province, April 12, 2014. (Xinhua/Liang Aiping) 

Tourists visit a garden of peony flowers in Xi'an, capital of northwest China's Shaanxi Province, April 12, 2014. (Xinhua/Liang Aiping)