1964 was a crucial year for Warhol: after a series of sold-out exhibitions, culminating in the "Brillo Box" exhibition at the Stable Gallery, the renowned gallerist Leo Castelli accepted Warhol into his artist squad. In the summer of 1964, Warhol conceived the "Flowers" series for his new gallery: Flowers in bright pop art colors on a deep black ground in a square format ranging in sizes from 5 to 45 inches. The exhibition at Castelli in New York opened in November of the same year, and the exhibition rooms were bathed in a sea of flowers. "The exhibition, his first with the gallery, was a milestone in his career, as his first attempt to exhibit at Castelli in 1961 was met with rejection.. Now he joined the gallery, which represented the crème de la crème of American avant-garde art, including leading figures like Robert Rauschenberg, Jasper Johns and Frank Stella." (Michael Lobel, "In Transition: Warhol's Flowers" in: ex. cat. Andy Warhol Flowers, Eykyn Maclean Gallery, New York 2012, no p.) For his first Castelli exhibition, Warhol did without the popular pictures of celebrities and consumer goods in favor of a potential future icon that was more timeless than contemporary. The flowers were based on a series of color photographs of seven hibiscus flowers shot by Patricia Caulfield and featured in the June 1964 issue of the magazine 'Modern Photography'. The photographer demonstrated different visual effects created by different exposure times and filter settings. The seriality of images in 'Modern Photography' undoubtedly spoke to Warhol's keen sensitivity to image repetition. However, instead of taking an entire page from the magazine, each with rectangular images of flowers, Warhol isolated and truncated a square composition containing four flowers from one of the reproduced photos. This way Warhol had more control of the conditions of reproduction, variation and manipulation in his paintings. The cutout was then transferred to acetate and its tonal range was polarized to increase sharpness and to create the perfect template for screen printing. Warhol chose the square format because it has a fixed orientation and offers four compositional possibilities. Today the "Flowers" are unmistakable Warhol products, however, back then they were considered a bold change of subject in his oeuvre. The "Flowers" are among Warhol's most popular series on the auction market and fetch top prices. A larger and to date most expensive version of "Flowers" fetched $15.8 million at Christie's in 2022. [SM]