Cunningham refined her style, taking a greater interest in pattern and detail and becoming increasingly interested in botanical photography, especially flowers. Between 1923 and 1925 she carried out an in-depth study of the Magnolia flower. In 1933, Cunningham founded the California Horticultural Society in which her images were so detailed and clear that many horticulturalist and scientists used her images in their studies. Later in the decade she turned her attention toward industry, creating several series of industrial landscapes in Los Angeles and Oakland.