A vendor prepares paan, a betel nut-based chewable stimulant at a flower market in Kolkata, India, January 18, 2016. (Photo by Rupak De Chowdhuri/Reuters)

Two railway workers chat in front of a flower mural inside a subway station visited by foreign reporters during a government organised tour in Pyongyang, North Korea October 9, 2015. (Photo by Damir Sagolj/Reuters)

Women, wearing traditional “ao dai” dress, pose for a photo next to peach blossom flowers ahead of Vietnamese “Tet” (the lunar new year festival) in a field in Hanoi January 22, 2017. (Photo by Reuters/Kham)

Soldiers pose for a photo during the flower exhibition marking the 105th birth anniversary of the country's founding father, Kim Il Sung in Pyongyang, North Korea April 16, 2017. (Photo by Damir Sagolj/Reuters)

A cyclist drives past a flowering rapeseed field not far from the small Bavarian village of Schoengeising, near Munich, during a nice, warm sunny weather day on May 17, 2017. (Photo by Christof Stache/AFP Photo)

To the woman presented a flower in Sevastopol, Ukraine, on March 8, 2013. Activists presented this day on the street free 155 tulips to women. The police tried to arrest activists for illegal trade as couldn't believe in free distribution of flowers. (Photo by Sergey Anashkevitch)

Coloured X-ray of a barn owl. A physicist has used X-ray to create an extraordinary collection of artwork. Arie van't Riets pictures reveal birds, fish, monkeys and flowers in an incredible new light. The 66-year-old, from Bathmen in the Netherlands, began X-raying flowers as a means to teach radiographers and physicians how the machine worked. But after adding a bit of colour to the pictures, the retired medical physicist realised the potential for an exciting new collection of art. (Photo by Arie van't Riet/Barcroft Media)

Visitors buy flowers at a flower market on the eve of Hindu goddess Durga Puja festival in Bangalore, India, 10 October 2016. The nine-day Hindu festival celebrates the killing of a demon king by the Goddess Durga representing the victory of good over evil and ends with colourful celebrations all over the country. Navratri festival runs from 03 to 11 October. (Photo by Jagadeesh N.V./EPA)