Abstract
Research reflective of the specific knowledge, skills, and abilities required to fulfill the job of a horticultural therapist is lacking. Past research indicated a majority of horticultural therapists agreed that a certification test is necessary for the advancement of horticultural therapy as a profession. The goals of this project are to identify the knowledge, skills, and abilities currently used and/or performed by horticultural therapists, as well as to use data to develop a generalized horticultural therapist job description based on current practice, to understand how the profession has changed since previous research was conducted, and to collect data to develop a certification exam. Job descriptions of horticulture-related occupations from the Department of Labor, therapeutic recreation job analysis components from the National Council for Therapeutic Recreation Certification (NCTRC), previous horticultural therapy job analysis information, and a concept analysis of membership-solicited job descriptions were used to construct a knowledge, skills, and ability survey. The web-based survey was sent to 227 current professionally registered members of the American Horticultural Therapy Association (AHTA). The questionnaire consisted of 95 items. A Likert-scale rating system was used by respondents to rate the importance of each item in their current profession. Eighty-five responses were acquired for a response rate of 37%. Survey respondents rated all statements of job knowledge, skills, and abilities presented at least “moderately important” for professional practice. The job task analysis is foundational to the establishment of future training requirements and in the development of a certification exam for horticultural therapy.
The Council on Licensure, Enforcement and Regulation, an international resource for professional regulation stakeholders, states the purpose of a job task analysis is to “define practice of a profession in terms of the actual tasks that new practitioners must be able to perform safely and competently at the time of licensure or certification” (Chinn and Hertz, 2010). Previous literature on horticultural therapy job analysis has focused on gathering demographic data and exploring relationships between academics, education, employment, salaries, and professional registration (Larson et al., 2010; Shoemaker, 2003; Stober and Mattson, 1993). This research has contributed to the understanding of the issues and challenges of horticultural therapy as a profession and has been used to develop a core body of knowledge and establish necessity of professional certification. Research on the specific knowledge, skills, and abilities required to fulfill the job of a horticultural therapist, however, is lacking.
The work of identifying and establishing the professional identity of horticultural therapists began in the 1950s, evolved through the 1960s, and was formalized as a profession in the 1970s with the establishment of the National Council for Therapy and Rehabilitation through Horticulture [NCTRH (Davis, 1998)]. In 1987, NCTRH formally became the AHTA. A job task analysis of the horticultural therapy profession was conducted in 1982 and gathered information about the knowledge, skills, and abilities required to perform specific job tasks and responsibilities required of a horticultural therapist (Kuhnert et al., 1982). That study provided an overview of a horticultural therapist’s job description and established the necessity of horticulture, therapy, and horticultural therapy education in the training of a horticultural therapist (Kuhnert et al., 1982). That same year, research conducted by Murphy (1982) explored certification exam development. The results of that research validated the results of the 1982 job task analysis, confirmed the need for a core knowledge requirement for horticultural therapy, and supported the need for a certification exam before registration to ensure competency. Stober and Mattson (1993) explored certification testing in a survey of horticultural therapists that indicated 50.6% of all respondents agreed a certification test is necessary for the advancement of horticultural therapy as a profession. Similar results were obtained in a survey published in the Apr.–May 1998 AHTA newsletter, People Plant Connection, demonstrating that of the 117 respondents, 61 were in favor of certification testing (Silberstein, 1998).
Certification has continued to be a point of discussion in subsequent research. Shoemaker (2002) compared horticultural therapy to other allied professions (therapeutic recreation, occupational, art, and music therapies). The comparative results highlighted the difference between the allied professions in membership, educational requirements, certification, and curriculum accreditation, and demonstrated that the horticultural therapy profession has not achieved the same level of professional recognition as the allied professions.
In 2003, Shoemaker published the results of a 2001 survey of AHTA professionally registered members in which respondents reported that knowledge of horticultural and plant sciences, which included botany, plant propagation, and horticulture, were necessary. Respondents also reported the need for general human services classes such as psychology, counseling, and human development. It was noted from this survey that professional recognition through certification or licensure was important for the future of horticultural therapy.
Larson et al. (2010) continued to build on earlier research that supported certification and analyzed the demographic information of AHTA membership at large in relationship to factors such as education, employment, and horticultural therapy training. The results of this research acknowledged the analysis of demographic information is only one component in the overall process toward the development of a certification exam.
The purpose of this study was to perform a job task analysis to identify the knowledge, skills, and abilities currently used and/or performed by horticultural therapists.
Methods
AHTA credentialing work team.
The work team was composed of six expert representatives of horticultural therapy, therapeutic recreation, medicine, and higher education. Work team members are all registered horticultural therapists and involved in different venues offering horticultural therapy with different populations with the exception of one, who is a practicing physician with a master’s degree in landscape architecture.
Survey development.
Using current job descriptions of horticulture-related occupations from the Department of Labor (O*Net, 2010a, 2010b, 2010c), the 2007 therapeutic recreation job analysis components [NCTRC, 2011], components of the 1982 job task analysis (Kuhnert et al., 1982), and a concept analysis of membership-solicited job descriptions, the work team constructed a survey to identify current professionally registered member’s knowledge, skills, and abilities.
AHTA sent an e-mail request to all professionally registered AHTA members and asked members to send horticultural therapy job descriptions to the AHTA headquarters to gather information about current job tasks. Fourteen job descriptions were submitted. Each job description was evaluated independently by two horticultural therapy experts to determine the centrality of horticultural therapy to the position. One job description was excluded because it did not refer to horticulture or horticultural therapy as part of the job title or description. The remaining job descriptions were analyzed and relevant knowledge, skills, and abilities were listed using concept analysis (Neuendorf, 2002). List items were rank-ordered and sorted based on the number of times they occurred in all job descriptions with one being the lowest and seven being the highest with the exception of one item, program development, occurring 13 times. All items occurring three or more times were included. All items ranked one and two, as well as the list of knowledge, skills, and abilities, were reviewed for synonymous terms and duplications were removed. Job tasks were then categorized as a therapeutic or horticultural skill.
Relevant items from the Kuhnert et al. (1982) job task analysis were integrated into all content areas of the current job task analysis. Additional horticulture information was determined through a review of job analyses retrieved from the O*Net (O*NET Online, 2010a, 2010b, 2010c). Job titles included Nursery and Greenhouse Managers, Landscaping and Grounds Keeping Workers, and Vocational Education Teachers, Postsecondary. A list of horticulture tasks and responsibilities were identified, modified, and incorporated into this job task analysis. Additional therapeutic tasks were obtained from a review of the 2007 job analysis conducted by NCTRC (2011). Specific knowledge, skills, and abilities applicable to horticultural therapy were identified and modified for inclusion in this current job task analysis.
Survey sampling and distribution.
The job task analysis was administered as a web-based survey. AHTA administered the survey through the online survey site, Survey Monkey (Palo Alto, CA), to 227 professionally registered AHTA members. The first e-mail request to complete the survey was sent on 1 Apr. 2013, with a due date of 20 Apr. 2013. A reminder e-mail was not sent. By 20 Apr. 2013, 56 professionally registered members had responded. The survey due date was extended through 30 Apr. 2013, and a second e-mail request was sent on 19 Apr. 2013. When the survey closed on 30 Apr. 2013, there were a total of 85 respondents for a response rate of 37%. This response rate is considered adequate given the size of the overall population of interest and the collection technique (Hamilton, 2003).
Job task analysis survey.
The survey was divided into three sections using the three identified knowledge areas from the 1982 job task analysis: horticulture, therapeutic, and other job responsibilities (Kuhnert et al., 1982). Each section was further divided into the categories of knowledge, skills, and abilities. The survey consisted of 95 items distributed between the three sections. A Likert-type rating scale (Likert, 1967) was created to determine the level of importance for each item.
Scoring of statements and sections.
Likert-scale responses were allocated points based on answers given with 0 points being allocated for no response, 1 point for answers of “not applicable,” 2 points for answers of “slightly important,” 3 points for answers of “moderately important,” 4 points for answers of “very important,” and 5 points for answers of “extremely important.” When necessary and based on individual statements, scoring for item statements were reverse coded/recoded to have higher values reflective of more positive answers. Missing answers were treated as missing data.
Statements were divided into categories based on related content knowledge, skills, and abilities. Scores for each respondent were generated for each section of the survey including statements relating to general horticulture knowledge (six statements, score range 0–30 points), general horticulture skills and abilities (seven statements, score range 0–35 points), landscape design, maintenance, and construction knowledge (four statements, score range 0–20 points), landscape design, maintenance, and construction skills and abilities (four statements, score range 0–20 points), floral and interior plant knowledge (two statements, score range 0–10 points), greenhouse and nursery knowledge (five statements, score range 0–25 points), greenhouse and nursery skills and abilities (two statements, score range 0–10 points), pest identification and management knowledge (three statements, score range 0–15 points), pest identification and management skills and abilities (two statements, score range 0–10 points), equipment skills and abilities (five statements, score range 0–25), and accessible/adaptable design, structures, tools, and equipment (three statements, score range 0–15 points).
Scores were also generated for items relating primarily to horticultural therapy including scores for therapeutic knowledge (19 statements, score range of 0–95 points), therapeutic skills and abilities (11 statements, score range of 0–55 points), horticultural therapy knowledge, skills, and abilities (seven statements, score range of 0–35 points), and other horticultural therapy job responsibilities (17 statements, score range 0–85 points). Higher scores indicated a greater importance of the category to each respondent.
Data analysis.
Data were automatically downloaded into an Excel (Microsoft, Redmond, WA) file and then analyzed using SPSS (version 21.0; IBM Corp., Armonk, NY). Statistical analysis included descriptive statistics, frequencies, and correlations.
Results
A Cronbach’s alpha reliability analysis determined the overall instrument to have high reliability (α = 0.97) (Gall et al., 2007).
Individual knowledge and skill set analyses.
Frequency and descriptive statistics were used to analyze perceptions of importance of individual knowledge and skill sets within each section of the survey. Overall, respondents ranked most items in most sections as being important for the career of horticultural therapist (Tables 1–6).
Frequency and descriptive data indicating survey responses from current professionally registered members of the American Horticultural Therapy Association to the question, “how important are the following therapeutic knowledge content areas to your job?”


Frequency and descriptive data indicating survey responses from current professionally registered members of the American Horticultural Therapy Association to the question, “how important are the following therapeutic skills and abilities to your job?”


Frequency and descriptive data indicating survey responses from current professionally registered members of the American Horticultural Therapy Association to the question, “specific to horticultural therapy knowledge, skills and abilities, how important are the following to your job?”


Frequency and descriptive data indicating survey responses from current professionally registered members of the American Horticultural Therapy Association to the question, “how important are the following horticulture knowledge content areas to your job?”


Frequency and descriptive data indicating survey responses from current professionally registered members of the American Horticultural Therapy Association to the question, “how important are the following horticultural skills and abilities to your job?”


Frequency and descriptive data indicating survey responses from current professionally registered members of the American Horticultural Therapy Association to the question, “how important are the following other horticultural therapy job responsibilities to your job?”


Therapeutic knowledge.
Nineteen statements measured the importance of therapeutic knowledge as a job skill. Overall, most of the therapeutic knowledge content statements were rated as “very important” to “extremely important” with an average mean of 4.12. The statement, “Identify and write goals and objectives,” was ranked as “slightly important” to “extremely important” by over 97% of respondents; therefore, the statement appears to be a main responsibility of most respondents (Table 1).
Therapeutic skills and abilities.
With an average mean of 3.82, most of the 11 statements on the therapeutic skills and abilities scale were ranked lower in importance on average when compared with the therapeutic knowledge statements. Similar to the therapeutic knowledge section, several items had ≈10% of respondents rating statements as “not applicable,” and others rating the same statements as “extremely important” (Table 2).
Horticultural therapy knowledge, skills, and abilities.
Seven statements asked respondents about the importance of various horticultural therapy knowledge, skills, and abilities. Again, most statements were rated as “very important” to “extremely important” with an average mean of 4.40. Two statements averaged lower, near 3.0, or near the “moderately important” level. These lower-ranked statements included one statement concerning administering performance tests, another related to conducting training (Table 3). Each of these statements also had more than 20% of respondents rating the statements as being “not applicable” to their situation.
Horticulture knowledge.
The importance of different types of horticulture knowledge was evaluated with 23 statements. Statements were divided into categories based on the relating concepts. All statement means of importance, in general, ranged as being “moderately important” to “extremely important” types of knowledge (with means between 3.0 and 5.0) with the exception of statements relating to nursery plant production, and nursery operations and management, which had means at 2.62 and 2.60, respectively. Furthermore, over 20% of respondents rated these statements as “not applicable.” However, understanding greenhouse operations and management was ranked as more important (3.37) in comparison with nursery operations knowledge. Having the knowledge to select appropriate plant material (4.52), understanding the toxicity of plant materials (4.48), and understanding accessibility issues and accessible structures (4.31) were ranked as the most important types of knowledge (Table 4).
Horticulture skills and abilities.
Twenty statements asked respondents to rank horticulture skills and abilities on the five-point Likert scale. All statements had means between 3.0 and 5.0 with the exception of the statements relating to operating vehicles and powered equipment, building hardscapes, and mixing pesticides. These lower rankings may reflect varied types of horticultural therapy practice since these statements also had over 20% of respondents rating the statement as “not applicable” (Table 5). For instance, those in vocational programs would most likely be performing these tasks as well as teaching clients safety skills in this area. Other horticultural therapists may never even use the equipment, as they practice on contract, or offer an activity-based program. Also, while understanding accessible structures was ranked quite high (4.31), the actual skill to construct structures was rated low (2.80), indicating that most horticultural therapists may contribute to design of garden structures, but are much less likely to build them. Professional contractors may perform construction at many program sites, and hired grounds crews may do mowing and other maintenance of grounds.
Other horticultural therapy job responsibilities.
Seventeen statements measured responsibilities related to other horticultural therapy job responsibilities. The mean scores for these statements were lower in comparison with other categories of scores and ranged from 2.68 to 3.88. Additionally, several items had 15% to 20% of respondents rating the items as being “not applicable” (Table 6). While several respondents feel it is important to have horticultural therapy knowledge, they rarely have a research component evaluating their own programs within their jobs. Several statements related to working in teams, while some horticultural therapists may be working independently.
Score comparisons.
Pearson product–moment correlation tests were completed between horticultural therapy knowledge, skills, and abilities; horticulture knowledge, skills and abilities; and other horticultural therapy job responsibilities’ scores. Significant positive correlations were found on all of the categories among all of the scores with the exception of the therapeutic knowledge overall score. Therefore, the therapeutic knowledge overall scores did not correlate similarly in importance with other overall score.
Additional comments.
Respondents were also given the opportunity to provide additional comments “to better understand the knowledge, skills, and abilities required by your job.” A range of responses were given, including positive, negative, and neutral comments. Positive comments included the feeling of being part of an overall team of treatment experts. Negative comments included those regarding responsibilities such as, “As a one-person program, I feel that I am being washed along, constantly overwhelmed by too much to do,” or those relating to limited awareness of the field and, therefore, limited recognition from insurance companies. Neutral comments included those mentioning that respondents wished for more information or resources regarding their job such as, “I would like more resources for grant info,” or suggestions that the career preparation extend to including nature education.
Discussion
Results indicated that survey respondents rated all statements of job knowledge, skills, and abilities presented at least “moderately important” for professional practice. This study can thus be used as a tool in the analysis of the content of each specific core course and elective topic in the professional registration standards. The applicability and the desirability of allowable course topic areas for future education requirements can be assessed.
Job task analysis is foundational to the establishment of future training requirements, as well as in the development of a certification exam for horticultural therapy. This study identifies job knowledge, skills, and abilities of the profession, and can serve as the basis for future creation of a testing instrument for certification. Effective and defensible credentialing exams are based on knowledge, and essentially how that knowledge is applied in the workplace. Identified as a desire of AHTA membership, an exam would provide assurance to the public and employers that a practitioner possesses specified knowledge, skills, and abilities, and would help to advance the profession of horticultural therapy (Silberstein, 1998).
Additionally, the statements in this survey present a basis to create an application for a horticultural therapist job description to be used in the U.S. Department of Labor’s 2018 edition of the Standard Occupational Classification and O*Net, their online database of occupations. Acceptance by the Department of Labor would increase the profile and awareness of horticultural therapy as an occupational option. Consequently, job description development and application to the Department of Labor by AHTA is recommended for the very near future.
Comparisons were made to determine if and how the practice of horticultural therapy has changed since the 1982 job task analysis (Kuhnert et al., 1982), even though this study included an expanded set of knowledge, skills, and abilities. In the 1982 study, the five top-rated job dimensions were motivation management, communication, horticultural skills, goal setting, and activity programming. These five job dimensions received the highest rankings for both importance and time spent. Each of these, except horticultural skills, was categorized under the domain of “therapeutic knowledge, skills, and abilities.”
In this study, horticultural skills include many areas, most of which received mean scores ranging from 3.06 to 4.52 (Tables 4 and 5). Horticulture skills continue to be necessary to the practice of horticultural therapy, with very little apparent change since 1982.
When statements from respondents in 2013 are compared with results under the domain of “therapeutic knowledge, skills, and abilities” from the 1982 study, there were some interesting similarities. For example, “principles of counseling techniques, behavioral interventions, motivational strategies” and “principles of group facilitation, motivation, and leadership” had mean scores of 4.34 and 4.40, respectively (Table 1), which are similar to the high rankings for “motivation management” and “communication” in the1982 study. The item statements of “activity/task analysis,” “adaptation of activities and intervention,” and “program design relative to population served” all received mean scores above 4.00 in this study (Table 1) and are similar to “activity programming” identified in the 1982 study. The item statement, “identify and write measurable goals and objectives” had a mean score of 4.15 in this study (Table 1) and can be compared with the highly rated “goal setting” in the 1982 study. Even with the restrictions of comparing the results of two noticeably different surveys, it appears that key areas of horticultural therapy practice have remained essentially the same for more than 30 years.
For a comprehensive analysis, an attempt was made to gather information about additional job knowledge, skills, and abilities important to the respondents. However, the open-ended responses received were mostly unrelated, as described in “methods,” and did not supplement the survey statements. Further study (perhaps in the form of interviews with representative stakeholders) may reveal additional areas of knowledge, skills, and abilities that were not quantified in the survey.
It is interesting to look at the statements with the lowest mean scores to understand which of the knowledge, skills, and abilities may be less critical for current horticultural therapy practice. Scores falling between 2.0 and 2.9 (or the equivalent of “moderately important”) included those regarding the administration of performance tests, knowledge of nursery operation and nursery plant production, the skill to perform pest/disease management, to operate vehicles and power equipment, and to build landscape structures. While performance testing may be a required job task in any type of horticultural therapy program, the other lower-scoring job skills are often necessary in the specialty of vocational horticultural therapy practice. Unlike activity-based programs, vocational horticultural therapy programs typically include horticulture production as a key component (Haller, 1998). It is unclear why these items received lower ratings. Perhaps vocational programs are less prevalent than other types of horticultural therapy practice, or those who work in vocational horticultural therapy programs may have been underrepresented in the respondent pool. Because the primary objective of this study was job task analysis, this survey did not gather demographic data from respondents, and therefore cannot compare responses by practice types. Further study is necessary to reveal any variations of job tasks required across the wide-ranging types of horticultural therapy practice.
Another indication of diversity of practice may be observed by looking at the “not applicable” responses over 10%. For most of these statements, the combined totals of respondents rating them as “moderately, very, and extremely important” were high. For every task except “operate vehicles and/or powered equipment,” responses of moderately important and higher were 50% to 80%, with only 20% to 50% rating them as “slightly important and not applicable” (Table 5). This shows that these job tasks were most often considered at least moderately important, even though many respondents considered them not applicable for their jobs. This may be due to the varied programs and settings in which horticultural therapy is practiced.
Conclusion
No clear current data exist about the practice types and settings of registered horticultural therapists. The entire population of 227 registered practitioners was sent the survey. The response rate of 37% (85 respondents) is presumed to accurately reflect the overall profession. However, further data are needed to verify that various practice areas, work settings, or other demographic characteristics are represented in the same proportions as in the entire population of registered horticultural therapists. Larson et al. (2010) did report on several professional characteristics among AHTA members, including data on education levels, practice identity, years of experience, area of work, and population served. Results indicated that AHTA members practiced most often in long-term care, rehabilitation, education, hospitals, vocational training, and landscape design. Note that it surveyed the membership at large, rather than the subgroup of those professionally registered. No other studies have collected this specific data. A complete job analysis surveying the professional registered members of the AHTA, combining demographic information and work-related knowledge, skills, and abilities, is recommended for future research. Suggested demographic data to collect includes major practice areas, job titles, work settings, geographic location, ethnicity, gender, education level, and work experience. In addition, the job analysis should survey stakeholders such as educators and employers.
This study identifies job knowledge, skills, and abilities in the practice of horticultural therapy, and provides data that indicates little change in these over the past 30 years. It offers a basis for a general job description of a horticultural therapist and information on key aspects of job knowledge upon which to base future educational requirements and begin the development of a certification exam for professional certification of horticultural therapists.
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