What is Horticultural Therapy?
Horticultural therapy uses plants and gardening activities to support human healing and rehabilitation. Unlike recreational gardening, horticultural therapy is a clinical practice facilitated by a registered horticultural therapist that involves structured, goal-oriented activities designed to achieve specific therapeutic outcomes within an established treatment or rehabilitation plan. Horticultural therapy techniques are employed to assist participants to learn new skills or regain those that are lost, helping improve memory, cognitive abilities, task initiation, language skills, and socialization; in physical rehabilitation, it can help strengthen muscles and improve coordination, balance, and endurance. Horticultural therapy is defined as the participation of a person in gardening-related activities with help of trained therapists, and is a subgroup of occupational therapy with the aim to achieve a specific treatment goal such as to improve the symptoms of posttraumatic stress disorder or depression.
Origins & Lineage
The therapeutic value of horticulture has deep historical roots: as early as 2000 BC, Mesopotamian cultures incorporated gardens and plant materials into practices intended to soothe and restore well-being, and by around 500 BC, Persian designers developed “paradise gardens” that engaged sight, scent, and sound to promote sensory comfort and reflection. The modern profession emerged in the 19th century when Dr. Benjamin Rush, a signer of the Declaration of Independence and recognized as the “Father of American Psychiatry,” was first to document the positive effect working in the garden had on individuals with mental illness.
The term “horto-therapy” was first used by Richardson Wright in 1945 while the term “horticultural therapy” was introduced by Ruth Mosher in 1948. In the 1940s and 1950s, rehabilitative care of hospitalized war veterans significantly expanded acceptance of the practice, and horticultural therapy practice gained in credibility and was embraced for a much wider range of diagnoses and therapeutic options. Alice Burlingame and Donald Watson helped formalize the field with their collaborative text Therapy Through Horticulture (1960), which became one of the first works to articulate horticultural therapy as a structured clinical practice.
The first academic degree specifically in horticultural therapy was awarded in 1972, and in 1973, practitioners formed the National Council for Therapy and Rehabilitation through Horticulture (NCTRH) to promote standards, training, and research. This organization later became the American Horticultural Therapy Association (AHTA), which remains the primary professional body establishing standards and credentials.
How It’s Practiced
Horticultural therapy sessions are structured interventions designed around individual treatment plans. In vocational horticultural therapy settings, people learn to work independently, problem solve, and follow directions. Activities may include seed starting, transplanting seedlings, soil preparation, pruning, harvesting, flower arranging, and tending therapeutic gardens. Each task is selected to address specific therapeutic objectives—fine motor skills might be developed through transplanting delicate seedlings, while upper body strength could be built through digging and raking.
Sessions are facilitated by credentialed professionals. Horticultural therapists are uniquely trained individuals who must fulfill academic coursework in both human development and horticulture science and they must hold a Bachelor’s degree, and they are required to complete a supervised 480-hour internship. Horticultural therapists are professionals with specific education, training, and credentials in the use of horticulture for therapy and rehabilitation.
The practice emphasizes process over product. While a beautiful garden may result, the therapeutic value lies in the sensory engagement, cognitive challenge, and physical movement involved in plant-related activities. Practitioners document participant progress using standardized assessment tools and treatment notes, similar to other allied health professions.
Horticultural Therapy Today
Today, horticultural therapy is accepted as a beneficial and effective therapeutic modality and is widely used within a broad range of rehabilitative, vocational, and community settings. Common settings include Veterans Administration hospitals, psychiatric facilities, rehabilitation centers, senior living communities, correctional facilities, schools serving students with disabilities, and outpatient therapy programs.
Professional credentials have evolved significantly. The Horticultural Therapist – Board Certified (HT-BC) certification officially began in fall 2026 when the board certification exam was launched. The Horticultural Therapist-Registered (HTR) recognizes professionals who have an education in both plant science and human science, and horticultural therapy with additional training acquired through an intensive internship experience in horticultural therapy, while the Therapeutic Horticulture Practitioner (THP) recognizes professionals with an education in horticultural therapy and work experience providing therapeutic horticulture services.
The profession has gained interest in other countries and regions including but not limited to Canada, the United Kingdom, Japan, South Korea, Israel, China, Hong Kong, India, Singapore, Australia, Peru, Spain and France.
Common Misconceptions
Horticultural therapy is not simply gardening for relaxation. Horticultural therapy and therapeutic horticulture are two sides of the same coin—the former more formal and the latter more informal, with patients gardening as part of a program versus someone in their backyard with their hands in the soil. Horticultural therapy is distinct from gardening or “forest bathing” because horticultural therapists are trained professionals who receive extensive education and training in the fields of horticulture and human science and are trained in specific therapeutic practices.
It is also distinct from therapeutic horticulture. Therapeutic Horticulture (TH) is a more community-based practice that can be facilitated by non-clinical professionals and volunteers that have received specialized training in TH, utilizing nature-based activities to support broader goals that address human health and wellbeing in a variety of settings, without the need for clinical oversight.
Finally, horticultural therapy is not a substitute for medical treatment but rather a complementary intervention used within comprehensive treatment plans. It requires documentation, assessment, and measurable outcomes like other clinical modalities.
How to Begin
For individuals seeking horticultural therapy services, the AHTA maintains a registry of credentialed professionals searchable by location. Many rehabilitation centers, hospitals, and senior care facilities now offer horticultural therapy programs as part of their therapeutic services.
For practitioners, an AHTA Accredited Certificate Program is a college-level educational program that offers the equivalent of nine (9) semester credits in horticultural therapy coursework, providing a foundation in the theory and application of horticultural therapy for diverse populations. The foundational textbook for the field is Horticultural Therapy Methods: Connecting People and Plants in Health Care, Human Services, and Therapeutic Programs by Rebecca L. Haller and Christine L. Capra, now in its third edition.
Those interested in experiencing the benefits without formal clinical intervention may explore therapeutic horticulture programs offered through community gardens, botanical gardens, or nature centers, which provide structured plant-based activities in less clinical settings.