The five-foot-tall painting, once owned by a haircare maven, offered a fresh test of the trophy art market.

In the Mekong Delta, farmers and locals still gather the flowers on wooden boats. Now, the ritual’s also become a photo op.

At the start of the traditional distillation process — which has been repeated for centuries — the petals are set in mud ovens and boiled with water; smaller copper pots sit above the roses to trap ...