Born in Buffalo, New York, Koch attended grade school at Buffalo public schools. Following her graduation from Michigan State College with a B.S. in 1909, she taught science for five years at Western State Teachers College in Kalamazoo, Michigan. Koch entered Cornell University in 1915 and graduated the following year with an M.A. degree. She then relocated to Poughkeepsie, New York, where she taught landscape gardening at Vassar College for two years. Koch returned to Cornell for a master’s degree in Landscape Design in 1918, also working as a graduate teaching assistant. Upon her graduation the following year, she joined the Botany Department at Smith College, where she remained a faculty member until her retirement in 1952. While there Koch developed an interdepartmental major in landscape architecture, served as a consultant to the president of the college on planning, and designed the Capen House gardens as well as the crab-tree plantings around the Alumnae House gardens. Koch also designed several private gardens in Northampton, Massachusetts, and was instrumental in the design and development of the city’s Sheldon Playground. She attended the International Town Planning Congress in Berlin in 1930 and traveled extensively in Europe, studying gardens and city planning, especially in northern European cities.
Koch served on Northampton’s initial planning board from 1924 to 1927 and the City Improvement Committee from 1927 to 1943. She served on the Northampton Planning Board from the time it was established in 1946 until 1966, becoming its chair in 1953. Koch was also a founding member of the American Horticultural Council and a member of the Massachusetts Planning Board. She passed away at the age of 88 in Williamsville, New York.