Therapeutic horticulture is a unique profession and practice that overlaps to some extent with the health/care and horticulture professional domains. The knowledge required to practice in this field is drawn from these overlapping sectors and from research in a number of other areas including psychology, physiology, neuroscience, environment, occupational therapy, social work and education. In these pages, we gather definitions, links to resources and associations, precis of research findings and updates on the evolving knowledge that underpins and helps our field develop and improve.
Courses
Trellis: Professional Development Award
Developing Professional Practice in Therapeutic Horticulture,SCQF Level 7 (awaiting approval, plan to start teaching 2025-26 in conjunction with 2 Scottish Colleges). Sign up for updates here.
Horticulture Therapy Institute, USA
Certificate Programme accredited by the US Association, the AHTA, comprises Fundamentals of HT followed by HT Techniques, HT Programming and HT Management.
University of Florida
AHTA accredited certificate course. Research and applied knowledge partnership with Wilmot Botanic Garden which runs comprehensive Therapeutic Horticulture programmes for a wide range of client groups
Internationale Gesellschaft GartenTherapie eV
German language courses at various universities in Europe, accredited by the IGGT
Thrive Diploma
The Thrive Diploma in Social and Therapeutic Horticulture aims to provide students with the knowledge and skills needed to deliver Social and Therapeutic Horticulture (STH) in any practice setting.
North Carolina Botanic Garden online course
Devised and taught by friend of Trellis and experienced practitioner, Emilee Weaver this 6 week course is a good foundation.
Associations & registers
UK – Association for Social and Therapeutic Horticulture (ASTH)
Created by Trellis in association with Thrive. Stay in touch with the Professional Development Forum, and help shape the future register, quality standards and the Association that hosts it.
USA - The American Horticultural Therapy Association (AHTA)
The most established in the world and a reference for many other associations.
Germany – the IGGT
A well established registration system and links to training courses at universities across the German speaking world.
Hong Kong - HKATH
Working to support the growth of the TH field, both in professionalism and in popularity. Training, support for professionals, research and promotion.
Japan - Japanese Society of People-Plant Relationships
The society is an academic research organization affiliated with the Science Council of Japan.
Australia – Therapeutic Horticulture Australia (THA)
Training, support and promotion.
Spain - AEHJST The Spanish Association for Therapeutic Horticulture
Training courses, conferences, and seminars. Support to professionals and organizations.
Canada - CHTA
Registering body with links to education and resources.
Databases:
Therapeutic Horticulture Activities Database (THAD)
Created in the USA by the University of Florida working together with several US TH networks -fantastic resource full of activity ideas tailored to different health needs and therapeutic goals -still in development but already so useful.
GarThePedia plant database
Developed by German therapeutic horticulturalists, lists an extensive range of plants with related activities, and relevant functional/therapeutic outcomes. Each plant record includes Latin and common names alongside any toxicology/allergy warnings, folklore, medicinal and culinary uses, and even cultural material such as poetry and song lyrics. Written in German originally but a programme of translation into English is underway.
Text books:
Horticultural Therapy Methods: Making Connections in Health Care, Human Service and Community Programs. Haller, R L & Capra, C L, (Eds), Taylor Francis 2008.
Rebecca Haller and Christina Capra are both actively involved as directors at the HTI in Denver, Colorado. A new edition will be published in 2025
Horticulture as Therapy: Principles and Practice, Sharon P Simson, Martha C Straus, CRC Press, 1998.
This book has sections on all disabilities, and ideas for therapeutic sessions.
Therapeutic Landscapes: An Evidence - Based Approach to Designing Healing Gardens and Restorative Outdoor Spaces, by Clare Cooper Marcus & Naomi A Sachs, Wiley, 2014.
Designing outdoor spaces for people with dementia. Pollock, A and Marshall, M. (eds.) Dementia Services Development Centre, 2012
Designing balconies, roof terraces and roof gardens for people with dementia. Mary Marshall, Dementia Services Development Centre, 2010.
Digging for Victory: Horticultural Therapy with Veterans for Post-traumatic Growth, Joanna Wise, Karnac Books 2015.
E O Wilson, Biophilia
Evidence base:
Trellis
We have collected studies of therapeutic gardening into a Research Library. This resource is not exhaustive but aims to be a source of evidence to support practice development and funding applications
Florida Horticulture for Health network
Horticulture for health has a very broad scope of activities, modalities, research and practice.
Networking Organisations:
- Trellis – you’ve already found us! Sign up to stay connected with practitioners and peers in the field
- Root in Nature – Canadian network
- THA – the Australian association also functions as a network
- World Therapeutic Horticulture Day, (WTHD) – we founded World TH Day partly to connect all the TH contacts we know around the world, and principally to raise awareness of the profession and its benefits. Join our World Day list if you’d like to be part of this big global network.
- European network of TH representative organisations – contact us for more information and watch their video here.
Design guidance:
Trellis Adaptive Design factsheet, Tabletop raised bed and Gardening with dementia factsheets. Contact us to enquire about our training in this area.
AEHJST - www.aehjst.org the Founders of the Spanish association have developed excellent design criteria for therapeutic gardens – contact Trellis more information.
Designing Outdoor Spaces for People With Dementia by Annie Pollock (Editor), Mary Marshall (Editor), Dementia Services Development Centre, & Hammond Care
Visual impairment design guidance - Gardening Within Arm’s Reach by Hans Schuman – a design resource focused on garden spaces for visually impaired children, from the author’s experience in schools in the Netherlands.
Websites:
Florida Horticulture for Health Network
A superb resource full of news, ideas, well-organised research digests, events, and a valuable, free monthly newsletter, CHIVE Talking compiled by experienced horticulture therapists and teachers.
Happiness is in the Garden
The blog for all those who believe that the garden can heal those who suffer.
Root in Nature
Canadian organisation providing training, inspiration, document templates, practitioner networking and more with some services free or pay as you go and some via a membership scheme.