Her work was first seen nationally at the 1939 New York World's Fair's American Art Today exhibit, where she displayed a Regionalist-style landscape in watercolor.
[3] In 1942 Tomkins and Fitzgerald returned to Seattle, moving back into a house in the Capitol Hill neighborhood which they had purchased and begun renovating in 1939.
That same year, a one-person show of twenty-three of her paintings was mounted at the Palace of the Legion of Honor in San Francisco alongside a solo exhibition of prints by surrealist artist Roderick Mead;[5] these works were also shown at the Seattle Art Museum.
[3] At this time, with only a handful of small galleries (such as Zoe Dusanne's and Otto Seligman's) showing modern art in Seattle, Tomkins was looking beyond the confines of the Northwest for both inspiration and reaction.
Tomkin's surrealistic biomorphism of the 1940s transferred creative internal energies into organic, visceral abstractions based on natural forms, a direction she continued to explore through the 1950s.
[7] In 1948 Tomkins and FitzGerald purchased several acres of land on Lopez, in the San Juan Islands, on which the family began constructing a summer home/studio using mostly natural, found, and recycled materials.
[8] The co-op of Tomkins, FitzGerald, Louis Bunce, William Ivey, Manuel Izquierdo, and Alden Mason managed to keep the gallery at 1705 E. Olive Way going for about a year.
She generally used a limited palette of grays, whites, and earth tones, with occasional flashes of red, blue, and yellow, developing an intricate symbolic language to express social and environmental concerns or reflect on personal experiences.
In 1973 FitzGerald died of bone cancer, and Tomkins took on the job of completing a 6,000-pound, 11-foot-high bronze fountain her husband had been commissioned to build.
[9] After FitzGerald's death Tomkins stopped exhibiting her work regularly, but continued painting, developing a more geometric, pastel-toned style.