The History of Horticulture as a Therapeutic Modality

It employs plants and gardening activities in therapeutic and rehabilitation activities to improve human wellbeing.  Historically, the use of horticulture to calm the senses dates as far back as 2000 BC in Mesopotamia. Around 500 BC, the Persians began creating gardens to please all of the senses by combining beauty, fragrance, music (flowing water) and cooling temperatures.

In the USA, the therapeutic benefits of peaceful garden environments have been understood since at least the 19th century. Dr. Benjamin Rush, considered to be the "Father of American Psychiatry" in the United States, reported that garden settings held curative benefits for people with mental illness.  A professor of the Institute of Medicine and Clinical Practice at the University of Pennsylvania known for his role in the development of modern psychiatry, Dr. Rush published his book Medical Inquiries and Observations Upon Diseases of the Mind in 1812. In it he stated that "digging in a garden" was one of the activities that distinguished those male patients who recovered from their mania from those that did not engage in garden activities.  Based on these observations, the hospital grounds included landscape-shaded paths through grassy meadows. Gradually in the United States, agricultural and gardening activities were included in both public and private psychiatric hospitals.

The use of horticulture to improve the care of veterans took a large step forward during WWI. The enormous number of returning wounded veterans to US hospitals precipitated the start of horticulture use in the clinical settings. Initially, horticulture was used for occupational and recreational therapy as part of psychiatric rehabilitation. The Rusk Institute of Rehabilitative Medicine, associated with New York University Medical Center, was the first US medical center to add a greenhouse to its rehabilitation unit in 1959 for interdisciplinary diagnostic and rehabilitative therapy.  In 1972 the Menninger Foundation teamed with the Horticulture Department at Kansas State University to provide training for undergraduate students in the mental health field. This would lead to the first horticultural therapy curriculum in the US.

Reference: What Is the Evidence to Support the Use of Therapeutic Gardens for the Elderly?
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3372556/