Horticultural Therapist-Registered (HTR)

The HTR is intended for practitioners who provide horticultural therapy services aligned with the AHTA definition:

  • The engagement of a participant in horticultural-related activities.
  • The participant has an identified disability, illness, or life circumstance requiring services.
  • The activity is facilitated by a registered horticultural therapist.
  • The participation is in the context of an established treatment, rehabilitation, or vocational plan.

The designation Horticultural Therapist-Registered (HTR) ensures that professional competencies have been achieved based on standardized academic requirements and professional training. Professionally registered horticultural therapists are expected to adhere to the AHTA Code of Professional Ethics for Horticultural Therapists. The AHTA's Standards of Practice for Horticultural Therapy describe the expectations of professional conduct and delivery of horticultural therapy service.

To be eligible to apply for professional registration at the HTR level, an applicant is required to: 

  • Be a member of AHTA as an Associate level One (1) or as an Associate Level Two (2)-year 3. 
  • Have a baccalaureate degree in horticulture with a concentration in horticultural therapy or an equivalent degree as defined in  the Professional Education requirements.
  • Applicants with advanced degrees in a horticulture or human science field approved by the AHTA are also eligible to apply.
  • Have successfully completed the required 480-hour internship in horticultural therapy or meet the work experience criteria defined in the AHTA Internship Handbook.  

View the HTR Policies and Procedures. 

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Please review all of the information on this page before applying.

Navigate this page:

Professional Registration Options
Internship Requirements
Academic Coursework Information
Professional Registration Application Process

Professional Registration Options

There are three options available to applicants interested in becoming professionally registered as an HTR with the American Horticultural Therapy Association. All options require coursework in plant science, human science, and horticultural therapy.

In addition to coursework, applicants are required to meet the internship or work life experience requirement. 

Option A: A baccalaureate degree in horticulture with a concentration in horticultural therapy.

A degree in horticulture with a concentration in horticultural therapy is defined as a horticulture degree that includes the required nine (9) semester credits in horticultural therapy coursework and the required twelve (12) credits in human science coursework.

If the degree program does not offer specific horticultural therapy courses, the nine (9) semester credits in horticultural therapy may be achieved by: 

1. Completing an AHTA Accredited Certificate Program. Courses may be transferred to meet the degree requirements. The transferable credits must be documented on the official transcript. All horticultural therapy coursework taken through a certificate program must be from an AHTA accredited program. 

2. Completing courses as an Independent Study. The independent study must be academic coursework reflective of the required course content in horticultural therapy and may not be hands on or work experience. 

Option B: An equivalent baccalaureate degree.

An equivalent baccalaureate degree is defined as a degree in a field other than horticulture that includes the full 33 semester credits of required plant science, human science, and horticultural therapy coursework as defined in Academic Coursework.

The required coursework may be in fulfillment of a degree or may be completed in addition to an existing degree. 

Option C: An applicant with a masters or doctoral degree in an approved plant science or human science field. 

An applicant with a masters or doctoral degree in an approved plant science or human science field is exempt from the undergraduate AHTA coursework requirements in their major. 

  • Approved plant science: Horticulture, Horticultural Science, Plant Physiology, Plant Science, Floriculture
  • Approved human science: Therapeutic Recreation, Occupational Therapy, Physical Therapy, Social Work, Counseling, Psychology, Rehabilitation Counseling

An applicant is required to complete the three (3) core courses plus one elective course identified in required coursework, a total of twelve (12) semester credits of undergraduate coursework in
a) human science if the advanced degree is in plant science or b) plant science if the advanced degree is in human science. 

All applicants applying under Option C must have the nine (9) semester credits in horticultural therapy coursework.

Internship Requirement

All applicants must successfully complete the required 480-hour internship or be exempt from the internship, must meet the work experience criteria. 

Review the AHTA Horticultural Therapy Internship section for full details and information. 

Grandfather clause 2013:  The AHTA updated the HTR education requirements in October 2013.  At that time, a grandfather clause was enacted. The grandfathering period is based on how many plant science and/or human science courses an applicant has taken prior to this date. Please review the grandfather clause to determine eligibility.

Academic Coursework Information

Grade:  All coursework must be for college credit. All coursework must have a passing grade of C- minus (C-) or above or a pass for a pass/fail course. 

Credit:  Review the HTR Policies and Procedures for more information about combining semester and quarter credits. For reference, review the Quarter to Semester Conversion Table for additional information. Coursework must be converted from quarter to semester credits at time of application.

Coursework granted credit for work and/or life experience by an accredited degree-granting institution will be accepted in fulfillment of the plant science and or human science course requirements. Please refer to Credit for Work/Life Experience for more information about this option.

Pre-approval:  The AHTA offers pre-approval of plant science and/or human science coursework for students considering applying for the HTR. To learn more about submitting a pre-approval application for coursework, please visit the Pre-Approval of Coursework for Professional Registration page.

Gandfather clause 2013:  The AHTA updated the HTR education requirements in October 2013.  At that time, a grandfather clause was enacted. The grandfathering period is based on how many plant science and/or human science courses an applicant has taken prior to this date. Please review the grandfather clause to determine eligibility.

Required Coursework:  The following coursework represents subject areas and not specific course titles. Please review the Course Titles that Support the AHTA Core Curriculum Topic Areas as a reference for plant science and human science course content descriptions with suggested course titles.

a) Plant Science: Twelve (12) semester credits total in: 

Three core required courses - a minimum of three (3) semester credits in each individual subject area:

  • Introduction to horticulture
  • Plant propagation
  • Pest and disease plant management

One elective course - a minimum of three (3) semester credits in one individual subject area:

  • General plant pathology
  • Greenhouse production/management
  • Nursery production/management
  • Landscape design
  • Plant materials
  • Soils

b) Human Science: Twelve (12) semester credits total in:

Three core required courses - a minimum of three (3) semester credits in each individual subject area:

  • General psychology
  • Abnormal psychology
  • Human lifespan development

One elective course - a minimum of three (3) semester credits in one individual subject area:

  • Counseling theories
  • Aspects of disabilities and illnesses
  • Group dynamics
  • Principles of therapy
  • Human anatomy/physiology
  • Adult development and aging

c) Horticultural Therapy: Nine (9) semester credits total in:

  • Horticultural therapy overview, introduction, or fundamentals
  • Horticultural therapy program management
  • Horticultural therapy skills, techniques, or practice
  • Horticultural therapy methods and programming
  • Human issues in horticultural therapy, people-plant relationships

 Horticultural Therapy Coursework

If the degree program does not offer specific horticultural therapy courses, the nine (9) semester credits in horticultural therapy may be achieved by: 

If the degree program does not offer specific horticultural therapy courses, the nine (9) semester credits in horticultural therapy may be achieved by:

1) Completing an AHTA Accredited Certificate Program.

2) Completing courses as an Independent Study. The independent study must be academic coursework reflective of the required course content in horticultural therapy and may not be hands-on or work experience. 

Horticultural therapy coursework completed as an independent study is required to cover the content areas as defined below. The following subject areas do not represent actual course titles. A course may include additional topic areas.

1. Overview of the profession to include:

  1. Definition of horticultural therapy
  2. History of horticultural therapy
  3. Program types – horticultural therapy and therapeutic horticulture
  4. Introduction to the American Horticultural Therapy Association
  5. AHTA Code of Ethics and AHTA Standards of Practice
    - Brief overview of the professional registration process 

2. Disability groups, characteristics and considerations, to include:

  1. Psychological (e.g., mental illness, substance use, attention deficit)
  2. Physical (e.g., spinal injury, orthopedic, cerebral palsy)
  3. Sensory (e.g., vision, hearing, sensory processing)
  4. Developmental (e.g., intellectual, autism, Down syndrome)
  5. Disease (e.g., cancer, dementia, stroke) 

3. Program materials, tools, and techniques, to include:

  1. Client assessment, evaluation, and documentation
  2. Goals and objectives for horticultural therapy clients
  3. Horticultural activities and activity modification
  4. Plant materials for horticultural therapy programs
  5. Adaptive tools, equipment, and devices
  6. Accessible indoor/outdoor horticultural therapy area (including consultation, site assessment, installation, utilization, and evaluation)
  7. Therapeutic garden characteristics and universal design 

4. Program management, to include:

  1. Short- and long-term program plans
  2. Horticultural therapy program proposals
  3. Program budgets
  4. Horticultural therapist role in multi-disciplinary team
  5. Volunteer resources and management
  6. Program promotion
  7. Funding resources, grants, and funding proposals
  8. Horticultural therapy research methods, evaluation, and outcomes

The document Course Titles that Support the AHTA Core Curriculum Topic Areas is the reference for plant science and human science course content descriptions. 

The AHTA Education section of the website lists colleges and universities that offer horticultural therapy as a degree option and lists AHTA accredited horticultural therapy certificate programs.

HTR Application Process

Ready to submit your application?  There are four components to complete an application for professional registration: 

  • Application
  • Internship Materials
  • Official Transcripts
  • Application fee

Please be ready to submit:

  • Academic information (identifying schools who will be forwarding transcripts).  
  • Internship information including a completed Internship Performance Report and a copy of either a) the Internship Case Study or b) Long-term Project. OR  Internship work-experience option: a letter verifying dates and hours of employment signed by the registered horticultural therapist supervisor.  
  • Internship information may also be sent to the AHTA office as a PDF email attachment (Internship Performance Report and/or supporting materials, or verification of work-experience letter).

Note: Official transcripts are required for all coursework. Unofficial transcripts, or unsealed transcripts, will not be accepted.

Transcripts: Three options:

  1. Official transcripts may be mailed directly to AHTA from the educational institution.
  2. Official transcripts may be sent to the applicant and mailed unopened by the applicant to AHTA.
  3. Official transcripts may be sent as electronic transcripts directly to AHTA from the granting school. Email AHTA.

Upon receipt of application, if there are any questions regarding the submitted coursework in the required subject areas, the review board will contact you and may ask for additional information. The application will be held and will not be processed until this information is received.

Review the HTR Policies and Procedures for complete information about the application review process. 

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