Human Health & Plants Research: Horticultural Therapy and Schizophrenia

Charlie GuyA newly published study in 2018 reported that horticultural therapy (HT) resulted in improvement of the psychopathological status of patients with chronic schizophrenia. A total of 28 schizophrenia patients were enrolled in the study. Participants were voluntarily assigned to either the control or the HT treatment group. The HT treatment consisted of two-hour horticultural activities once each week for ten weeks conducted during the spring that included cultivating beds for transplanting young plants, watering, mulching, weeding, fertilizing and harvesting.  Participants in the concurrent control group received no additional intervention beyond their ongoing psychiatric care. The experimental design included pre- and post-intervention psychiatrist evaluations, using the Brief Psychiatric Rating Scale (BPRS), and the Positive and Negative Syndrome Scale (PANSS Korean version). The BPRS assesses 18 symptom constructs and is very useful in gauging the efficacy of treatment in patients with moderate to severe psychoses. The PANSS is an assessment that gauges symptom severity of schizophrenia patients. The HT group following treatment showed a 35% improvement for the BPRS assessment, while the control group exhibited only a 5% improvement. The change in the BPRS score was robustly statistically significant for the HT group, but not for the control group. Similarly, the HT group exhibited improvements of 10%, 22% and 15% on the PANSS positive, negative, and general scales respectively, while the control group showed virtually no change for the three scales. The authors conclude that HT resulted in positive outcomes regarding the psychopathological symptoms of schizophrenia, and justify further trials with larger participant populations.

Oh YA, Park SA, Ahn BE (2018) Assessment of the psychopathological effects of a horticultural therapy program in patients with schizophrenia. Complementary Therapies in Medicine, 36: 54-58.

Charlie Guy, Professor, UF Department of Environmental Horticulture


Click here to return to the Wilmot Gardens’ Newsletter