Which 1920s Georgia O'Keeffe painting series depicts calla lilies?

Georgia O'Keeffe's Calla Lily series depicts calla lilies in enlarged, simplified forms. She repeatedly painted the flowers during the 1920s, turning their curving petals and central spadix into monumental modernist compositions.

O'Keeffe became especially known for enlarging flowers so that viewers had to confront their structures at close range. She rejected the idea that these paintings should be reduced to literal symbolic readings and emphasized the visual experience of seeing a flower at a large scale.

The Calla Lily works are often confused with her Red Canna or Black Iris paintings because all use close-up floral forms. Their subjects are different: calla lilies have a distinctive trumpet-like sheath, while the canna and iris belong to separate flower groups.