Horticultural therapy (HT) is the use of indoor and outdoor gardening as a therapeutic intervention and rehabilitative medium. To quote from the American Horticultural Therapy Association (AHTA) website:
Horticultural therapy techniques are employed to assist participants in learning new skills or regaining those that are lost. Horticultural therapy helps improve memory, cognitive abilities, task initiation, language skills, and socialization. In physical rehabilitation, it can help strengthen muscles and improve coordination, balance, and endurance. In vocational horticultural therapy settings, people learn to work independently, problem-solve, and follow directions.
The term “therapeutic horticulture” denotes the same activities with a lesser degree of therapeutic goal-setting, progress evaluation, and documentation.