Horticultural therapy (also known as social and therapeutic horticulture or STH) is defined by the American Horticultural Therapy Association (AHTA) as the engagement of a person in gardening and plant-based activities, facilitated by a trained therapist, to achieve specific therapeutic treatment goals. The visual aesthetics of plants are known to elicit feelings of inner peace, which generates positive emotions toward a meaningful appreciation of life. Direct contact with plants guides the individual's focus away from stress enhancing their overall quality of life. The AHTA believes that horticultural therapy is an active process which occurs in the context of an established treatment plan. Horticultural therapists are specially educated and trained members of rehabilitation teams (with doctors, psychiatrists, psychologists, occupational therapists and other) who involve the client in all phases of gardening, from propagation to selling products, as a means of bringing about improvement in their life.
The usage of horticulture to calm the senses dates as far back as 2000 BC in ancient Mesopotamia, and around 500 BC, ancient Persians created gardens to soothe the senses by involving beauty, fragrance, flowing water, and cool temperatures.  According to the American Horticultural Therapy Association, Ancient Egyptian physicians prescribed walks around a garden for patients with mental illness; which makes the first sign of the therapeutic process in Alexandria and Ancient Egypt through Renaissance Europe. During the Middle Ages, on the grounds of a monastery hospital, plants were used to express purpose of cheering up melancholy patients. Also, the gardens were used to treat both physical and mental ailments of sickness who visited them. The first modern documentation of horticulture being used as a treatment for mental health purposes was in the 1800s. Dr. Benjamin Rush discovered that field labor in a farm setting helped attain positive outcomes for clients with mental illness (Simson & Straus, 2003). This discovery lead many hospitals in the western world to begin using horticulture as a means to start therapeutically treating patients with mental health and developmental disabilities. In 1817, the Asylum for Persons Deprived of Their Reason, now known as Friends Hospital, constructed an environment with landscaping, paths and a park atmosphere in effort to assist patients in their recovery. In 1879 Friends Hospital built the first greenhouse that was used for therapy (Simson & Straus, 2003). “During World War I and II, servicemen worked in gardens to improve functioning of injured limbs and increase mental function, but also to learn new skills and to provide food. Plants and gardening also came to be used as a diversion for those who were hospitalized long-term.
The 1950s and 1960s brought the first degree in horticultural therapy at Michigan State University. In 1972, Kansas State University created the first curriculum that provided students with dual training in both psychology and horticulture (Simson & Straus, 2003). The first graduate degree program was offered by Clemson University in 1973 (Simson & Straus, 2003). In 1973 the Council for Therapy and Rehabilitation through Horticulture (NCTRH) was established by a group of horticulture therapy professionals. In 1988, they changed their name to the American Horticulture Therapy Association (AHTA) which they are still called today. AHTA is a non-profit organization with about 25% off their members being professionally registered.
Today, horticultural therapy is practiced in many countries and area in the world, such as in Japan, Korea, Hong Kong, the United Kingdom, Germany, Italy and Sweden. Many universities in these countries have education programs and research in horticultural therapy. Special laboratories have also been built, such as Alnarp Rehabilitation Garden at the Swedish University of Agricultural Sciences campus area in Alnarp.
American Horticulture Therapy Association (AHTA) offers the opportunity for professionals interested in practicing horticultural therapy to register as Horticultural Therapists (Horticulture Therapy Registered, HTR). Some colleges and universities have academic programs in horticulture therapy that are accredited through AHTA. AHTA has a set core curriculum for accredited programs to follow. Along with specific classes to take, internships are a very critical component. AHTA requires that to be Horticultural Therapist Registered, 480 hours of field experience are to be completed under supervision of a professionally registered horticultural therapist.
Summary: The significant positive association with gardening was observed for a wide range of health outcomes, such as reductions in depression and anxiety symptoms, stress, mood disturbance, and BMI, as well as increases in quality of life, sense of community, physical activity levels, and cognitive function. The positive effect were particularly evident regarding patients and horticultural therapy (0.61, Hedges' g). The researchers conclude that their meta-analysis has provided robust evidence for the positive effects of horticultural therapy on health.
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- "American Horticultural Therapy Association Definitions and Positions" (PDF). Archived from the original (PDF) on 2013-09-08.
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- admin (2019-02-18). "Discover Whether Horticultural Therapy Can Finally End The Torture of Being a Mental Illness Victim?". Olmec Agro-Tech. Retrieved 2019-03-19.
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- American Horticultural Therapy Association https://www.ahta.org/mission-vision. Retrieved 4 July 2019. Missing or empty
- Hong Kong Association of Therapeutic Horticulture http://www.hkath.org/en/milestone/. Retrieved 4 July 2019. Missing or empty
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