People enjoy orchids during the Orchid Show in Frankfurt, Germany, on April 5, 2013. (Xinhua/Luo Huanhuan)

People enjoy orchids during the Orchid Show in Frankfurt, Germany, on April 5, 2013. (Xinhua/Luo Huanhuan)

People enjoy orchids during the Orchid Show in Frankfurt, Germany, on April 5, 2013. (Xinhua/Luo Huanhuan)

People enjoy orchids during the Orchid Show in Frankfurt, Germany, on April 5, 2013. (Xinhua/Luo Huanhuan)

People enjoy orchids during the Orchid Show in Frankfurt, Germany, on April 5, 2013. (Xinhua/Luo Huanhuan)

People enjoy orchids during the Orchid Show in Frankfurt, Germany, on April 5, 2013. (Xinhua/Luo Huanhuan)

People enjoy orchids during the Orchid Show in Frankfurt, Germany, on April 5, 2013. (Xinhua/Luo Huanhuan)

People enjoy orchids during the Orchid Show in Frankfurt, Germany, on April 5, 2013. (Xinhua/Luo Huanhuan)

People enjoy orchids during the Orchid Show in Frankfurt, Germany, on April 5, 2013. (Xinhua/Luo Huanhuan)