The daughter of oboist Robert Bloom, Kath grew up in New Haven, where she studied the cello as a child and started playing the guitar when she was a teenager. She collaborated with Bruce Neumann in the early '70s, but it wasn't until she met avant-garde guitarist Loren MazzaCane Connors in 1976 that she started recording. Bloom and Connors recorded multiple albums of fragile, simple folk and blues melodies, the majority of which were written by Bloom herself. Their collaboration ended in 1984 with the release of their final album, Moonlight, of which only 300 copies were pressed.
Bloom stopped recording new material soon after her collaboration with Connors ended, and a period of financial hardship followed. A single mother, Bloom focused on raising her children, rarely playing shows outside of New Haven. Director Richard Linklater discovered Bloom's music sometime in the early '90s and subsequently featured her song "Come Here" in his 1995 film, Before Sunrise. Encouraged by Linklater's interest in her music, Bloom started writing new songs and released her first album in over ten years, Come Here: The Florida Years, in 1999.
Presently Kath trains horses and plays with her band Love At Work, which includes longtime collaborator Tom Hanford and husband Stan Bronski, offering a musical tour de force of programs for children and adults, as well as playing solo shows in the Northeastern US.