Isabella Preston was a horticulturist and public servant widely recognized for her achievements in plant hybridization and extensive work in ornamental plant breeding. During her 26-year career, she produced nearly 200 new hardy hybrids of lily, lilac, crab apple, iris and rose plants for Canada's cold climate. While female plant breeders were rather rare in her day, she quietly challenged gender bias and set the stage for new generations of breeding programs at the Central Experimental Farm in Ottawa, Ontario, Canada and elsewhere.