What is Horticultural Therapy?

The American Horticultural Therapy Association defines the practice of HT fairly narrowly, as participation in horticultural activities facilitated by a professional to support specific treatment or program goals.

I define horticultural therapy more broadly as an informed and intentional engagement with plants and nature to restore, enhance and support health, work, and learning.

Either way it's an evidence-based practice with well-documented effects that include:

  • Stress reduction. It is common today for people to experience stress for sustained periods without relief. Stress has become a major risk factor for many common disorders, among them mental illness, cardiovascular disease and other non-communicable diseases. Several studies have demonstrated a significant, measurable and lasting reduction in stress in response to views of nature or immersion in natural settings.*
  • Enhanced social cohesion. Other studies focus on the negative impact of social isolation on health, measuring it at the same magnitude as smoking cigarettes. Importantly, green spaces in built-up urban environments foster healthful social interaction.**
  • Improved cognition. Still others have studied the effects of nature on the ability to learn and understand. Evidence suggests that children's cognitive development is enhanced within a green environment. Schoolyards with high levels of vegetation seem to promote cooperation, attention skills, and creativity. There is evidence, too, that for elderly individuals, being able to view, experience, or interact with nature has a positive impact on both anxiety and dementia, as well as associated aggressive behavior.***

I do not see horticultural therapy as a stand-alone treatment. Rather, it provides a basis for which all other medical treatments can be more fully effective. It can have positive applications in other fields as well, among them education, urban planning and human resources. When people's stress is reduced, their propensity for social interaction facilitated and their cognitive skills supported, they are in an ideal state to heal, learn, or work more productively.


*McEwen & Stellar, 1993; Crestani, 2016. **Pantell, Rehkopf, Jutte, Syme, Balmes, & Alder, 2013. ***Studies by Dadvand, Nieuwenhuijsen, Esnaola, Forns, Basagaña, Alvarez-Prdrerol et al., 2015, Fjørtoft & Sageie, 2000; Mårtensson, Boldemann, Blennow, Söderström, & Grahn, 2009, Dzhambov & Dimitrova, 2014, and Chapman, Hazen, & Noell-Waggoner, 2007