Focusing on the The garden of Saint-Paul Asylum, Saint-Rémy (Van Gogh series), analyze the Vase with Irises about the Floral still life.
Vase with Irises In one of the iris paintings he places the large bunch of violet irises against a harmonious pink background.  Unfortunately, over time, the pink background has faded to almost white.  In the other, he use a contrasting yellow background.