Horticultural Therapy Program for People with Severe Mental Illness

This paper reviews the evidence-based practice of horticultural therapy (HT) for people with severe mental illness. We conducted a pilot study which showed that HT group could reduce stress and anxiety in participants. Based on the experience in the pilot study, we developed an 8-session horticultural therapy group and conducted a mixed method evaluation. The participants are people with severe mental illness who are attending day or work rehabilitation programs, and the outcomes of the therapy group is compared with a treatment-as-usual group. The mixed method study showed that horticultural therapy could increase occupational engagement, well-being, sense of accomplishment of participants; reduce anxiety among participants; but did not improve social interaction among participants. Many participants said they were amazed at the vitality and resilience of plants and were enthusiastic in learning more about horticulture. From the perspective of Model of Human Occupation, horticultural therapy could impact on the volition of participants, by raising their interest and promoting their personal causation in the activity. The therapeutic environment in horticultural therapy provide opportunities for successful application of process skills in occupational performance, but did not made an impact on communication skills or interaction among participants. We compared the study results with studies and reviews on HT horticultural therapy in other countries. The quality of HT programs could be improved by the development of standard protocols in HT; use of a combination of indoor and outdoor activities; and engaging therapists in formal training in HT. Therapist should design HT programs with a focus on only a few therapy objectives, such as promotion of mindfulness, appreciation of nature and plants, increasing engagement, and promoting a sense of meaningfulness and accomplishment. The sharing of log-books, reflective writing, and group sharing appeared to be important elements in enhancing the therapy effects. There is also a need to improve the quality of evaluation studies on HT.