Born in Brooklyn, New York, Ireys worked at the Brooklyn Botanic Garden as a young woman, which fostered her love of plants and gardens from an early age. After graduating from the Cambridge School of Architecture and Landscape Architecture in Cambridge, Massachusetts in 1935, she worked for landscape architect Marjorie Cautley for a year, and subsequently for Charles Lowrie, co-founder of the American Society of Landscape Architecture. After his sudden death in 1939, Ireys took over his practice and completed the Red Hook housing project in Brooklyn. She worked from Lowrie’s office until 1943, primarily producing landscape plans for public housing projects, public playgrounds, and college campuses in New York City, often alongside Cambridge alumnae, Cynthia Wiley and Clara Coffey. In 1943 she married Henry Tillingast Ireys III and opened an office in her home, where she worked until her death. Ireys spent much of the late 1950s to early 1980s teaching at the Landscape Design schools run by the Federated Garden Clubs. From 1952 to 1955 she designed what may be her most well-known work, the Garden of Fragrance for the Blind at the Brooklyn Botanic Garden. It was the first public garden in the country designed for the visually-impaired, and in 2001 it was renamed the Alice Recknagel Ireys Fragrance Garden.
Central to Ireys’ designs were plants that could be both beautiful and realistically maintained. She authored several books, including How to Plan & Plant Your Own Property (1967), Small Gardens for City and Country (1978), Garden Designs (1991), and Designs for American Gardens (1991). In 1978 Ireys became a Fellow of the American Society of Landscape Architects. She passed away at the age of 89 in Manhattan.