Horticultural therapy is defined through the American Horticultural Therapy Association (AHTA) because engagement of an individual in gardening in addition to plant-based activities, facilitated by way of trained therapist, to attain specific therapeutic treatment method goals. The AHTA is convinced that horticultural therapy is an active process which occurs in the context of a proven treatment plan. Simson and Straus have categorized Horticultural Therary services into three main kinds of programming; vocational, social and therapeutic.