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Contribution & Volunteering
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Dr. Candice Shoemaker, Chair
Dr. Andy Kaufman, Vice-Chair/Communications

Background and Definitions

Horticulture: Meeting the Needs of Special Populations

Diane Relf* and Sheri Dorn *

In the past five to ten years, there has been increasing research of the healing, social, and therapeutic benefits that plants impart to human life. With all of the resultant new information, people have become confused by the many facets of people-plant interactions, including the meaning of horticultural therapy. Much of this mismatching and misunderstanding has occurred at the university level as horticulture faculty members, well-versed in crop production and basic science, have begun to try to understand and share with students the value of horticultural commodities to the consumer. Horticultural therapy frequently is used as the catch-all phrase applied to anytime anyone gardens and feels better, acts better, or gets better under any conditions. In some situations, it has been the term of choice to apply to children's gardening, home food production in developing countries, and hobby gardening practiced by individuals with a disability. The restorative value of views of plants and nature also have been lumped into horticultural therapy, as has the social value of community gardening. Although horticultural therapy is a very important aspect of human interaction with plants, and is a rapidly growing profession, there are many other areas of people-plant interaction of equal importance to understanding the role of horticulture in addressing special populations.

It is the purpose of this special issue of HortTechnology to explore some of the different elements of people-plant interaction, such as healing, social, and therapeutic aspects, that address individuals with special needs, as well as to discuss horticultural therapy in-depth, and to provide the reader with resources to develop teaching, research, and extension programs for these individuals.


It will be helpful to first define the term "individual with special needs." This term refers to persons who might benefit from participation in horticultural activities or from viewing plants and landscapes, but who requires special adaptations or modifications for this to occur. These special adaptations may be required because of physical, mental, or social (including economic) limitations that prohibit the individual from acting on his/her own without assistance.
To understand the application of horticulture to individuals with special needs, the discussion is divided into the following topics:

Enabling or Accessible Gardens - Both public and private gardens can be made significantly more useful to individuals with disabilities. This involves not only more appropriate designs, but also incorporation of tools, techniques, and plant material selected to enhance gardening for the more than 55 million Americans with disabilities. The Americans with Disabilities Act mandates that public gardens become accessible to those with disabilities.
Children's and School Gardening - Whether or not a child has a physical or mental disability, involvement with plants has become a very limited experience for most of America's youth. Many arboreta and botanic gardens, Cooperative Extension, and other agencies and non-profit groups are beginning to address this population with its unique needs. Children with special needs, including youth-at-risk, have been targeted to participate in gardening programs.
Healing Landscapes - In the design of landscapes for hospitals, nursing homes, and hospices, the presence of plants is considered to be the healing element rather than part of a treatment program in which active participation with plant culture is integral to the therapy. These landscapes may be designed cooperatively with a horticultural therapist to serve the dual purpose of a healing landscape for some clients and a horticultural therapy garden for others. This field is becoming an increasingly recognized element in landscape design.
Garden/Plant Therapy - Garden clubs, Cooperative Extension Master Gardeners, and other volunteer groups have long been involved in bringing gardening to individuals who otherwise would not have such an opportunity. As volunteer-based activities, garden therapy programs frequently are not part of the treatment processes per se, but are valuable additions when conducted cooperatively with professional staff.
Horticultural Therapy (HT) - The profession of horticultural therapy is one of the treatment modalities (including art therapy, music therapy, and recreational therapy) that form the adjunctive therapy treatment approach. Horticultural therapy programs are found in psychiatric hospitals, physical rehabilitation facilities, educational centers for individuals with intellectual impairments, and similar treatment facilities. Professional horticultural therapists also work in vocational training programs, sheltered workshops, and prisons. In addition, arboreta and botanic gardens are employing Registered Horticultural Therapists to conduct educational outreach programs for professionals and clients in treatment facilities in their communities.
Human Issues in Horticulture (HIH) - HIH looks at the influences of plants on people in all aspects of their lives, regardless of special needs of the individuals. Other terms used to refer to this broad concept include socio-horticulture, people-plant interaction (PPI), and human dimensions in horticulture. HIH includes all of the above areas of concern, plus economic and marketing issues; physical and environmental amelioration by plants; food and nutrition; ethnobotany considerations as they apply to horticulture; and the role of horticulture in art, music, drama, and philosophy, as well as other issues.

Resources and Literature Review

In recent years, there has been a significant increase in the amount of information available in each of the areas that address horticulture and its applications to special populations. This information is spread widely among associations, books, and articles in professional journals and lay publications. Accessing this information may be facilitated by the following discussion.

Enabling or Accessible Garden

Millions of individuals with disabilities garden or would garden if given greater accessibility to tools and techniques that would facilitate this hobby. The fact that a person has a disability and participates in horticulture should not be taken to mean that they are involved in horticultural therapy. Having a disability does not require that all future daily life activities be considered therapy. Once persons have completed rehabilitation or therapy treatment, the term is no longer applied to their activities. In recent years, numerous books (Cloet and Underhill, 1990; Please, 1990; Yeomans, 1992; Adil, 1994; Rothert, 1994) and articles (Beems, 1985; Neace,1985; Bubel, 1990; Relf, 1994) have been published, targeted to gardeners with disabilities. With our rapidly aging population, this will be a growing area of concern. The horticulture industry is beginning to recognize the potential of this market, thus a few relevant articles have appeared in trade publications (Fuller, 1993; Saunders, 1994).

Several arboreta and botanic gardens have demonstration gardens that assist individuals with disabilities in developing home gardens. In addition, many arboreta and botanic gardens, recognizing the need to include disabled, elderly, and disadvantaged individuals in their programs and addressing the requirements of the Americans with Disabilities Act, are making buildings, grounds, and display areas accessible, and expanding the scope of their existing educational programs to make them of interest and value to special populations.

The Friends of Horticultural Therapy, a support organization of the American Horticultural Therapy Association (AHTA), has as one of its areas of concern making gardening more accessible to everyone. They promote horticultural therapy by publicly advocating and providing information about making the garden more accessible to disabled individuals.

Children and School Gardening

The children's gardening movement has gained significant momentum in recent years (see side bar C) through such efforts as the National Gardening Association's Grow Lab educational program. Their school gardening grants, consisting of tools, seeds, and garden products valued at an average of $500, are available to 300 programs nationwide. The American Horticultural Society has sponsored national conferences targeting school gardening. There are other outstanding national programs for integrating gardening into the elementary school curriculum, including Life Lab (sponsored by the National Science Foundation), and small businesses, such as Gardens for Growing People, dedicated to supplying children's gardening resources. A plant selection guide for children's environments (Moore, 1989) expands the concepts of how plants are used in the landscape.

A number of horticulture industry groups, businesses, and botanic gardens have been involved in supporting children's gardening. In addition, Cooperative Extension has taken a leadership role in this area, both in 4-H programs (Whittlesey, Curtis, and Laine, 1991) and through Master Gardener efforts, such as the Virginia Beach 4-H Urban Gardening Project entitled Ready Set Grow (Virginia Cooperative Extension, 1990).

Although the broad concept of children's gardening does not fall under the horticultural therapy umbrella, there are horticultural therapy programs that specifically address children in hospitals and other treatment settings (Kavanagh and Chambers, 1995). In addition, children's gardening programs from arboreta and botanic gardens may include horticultural therapy in treatment facilities or simply accessible gardening for disabled youth (Morgan, 1989; Moore, 1989).

Community Gardening and Urban Greening

Community gardens are particularly important to the elderly, disabled, and disadvantaged individuals in urban areas. Most often, the community garden is developed under the leadership of a group, such as the Pennsylvania Horticulture Society (Bonham, 1988, 1991), the Chicago Botanic Garden (Brogden, 1991), or other not-for-profit associations (Carrier, 1985) interested in horticulture and using it to improve the quality of life and the appearance of the community. These gardens are located near the people who need them and are run by the people of the community (Dotter, 1994; Keller, 1994; and Mattson et al, 1994). The Cooperative Extension Service of the U.S.D.A. has been influential in establishing community gardens in order to improve the nutrition of the people gardening, to develop leadership skills among these people, and to help them improve their communities in many other ways (Patel, 1991). Other organizations, such as the American Community Gardening Association, have resources available for assistance in establishing community gardens.

Healing Landscapes

The concept of designing landscapes at hospitals, hospices, and similar sites for their healing qualities rather than merely to cover the grounds is gaining prominence as a result of the work of Ulrich (1984) and the Kaplans (1989) which provide much of the theoretical basis for this movement. Francis et al (1994, 1994) has drawn together proponents of this concept for an exchange of ideas that has led to two sets of proceedings. The January 1995 issue of Landscape Architecture Magazine (4401 Connecticut Avenue NW, 5th floor, Washington, DC 20008-2302; tel: 800-787-LAMS) provides an overview of the current state of the art, as landscape architects continue to explore both healing landscapes and therapeutic garden design for horticultural therapy (Dannenmaier, 1995; McCormick, 1995; Stevens, 1995a, 1995b; Leccese, 1995; Sutro, 1995; Warner, 1995; Kavanagh and Musiak, 1993). The uniqueness of landscape design for nursing homes and other housing facilities for elderly and disabled persons is becoming internationally recognized (Stoneham and Thoday, 1994).

Garden/Plant Therapy

Volunteers have been essential in conducting horticultural therapy programs and historically volunteers have started many programs that went on to become part of the professional adjunctive therapies. Alice Burlingame (1974; Watson and Burlingame, 1960), a leader in the field of volunteering in HT, helped volunteers work with occupational therapists, physical therapists, and other professionals who were not familiar with plants but could see the potential benefits to their clients and wanted to add this tool to their therapeutic activities. Garden clubs traditionally have held garden therapy as one of their major areas of interest, such as Gardening from the Heart, a program of the Gardeners of America, Inc. (formerly the Men's Garden Clubs of America, Inc.). It is their "mission to extend, as well as advice, current and additional clubs in the formation of a horticulture therapy partnership, extending gardening to youth or adults who are disadvantaged, handicapped, retarded or mentally ill, as well as to residential elderly, including veterans" (Gardeners of America/Men's Garden Clubs of America, Inc., c.1990). One of the most important new contributors to volunteering in HT is the Cooperative Extension Master Gardeners (Flagler, 1992; Patel, 1991) The contribution of volunteers is so important that AHTA has a national award for outstanding volunteer efforts.

Horticultural Therapy (HT)

The profession of horticultural therapy is relatively new compared to the other therapeutic and caring professions. Under the leadership of the AHTA (see article in this issue), there are professional registration and development opportunities that make this a valued and dynamic area. Relatively few books have been published that directly address the development of HT programs and the therapeutic activities involved (Daubert and Rothert, 1981). However, as a large number of professionals have gained 15 or more years of service, new books should appear, such as a recent one from Canada (Hewson, 1994). Members of the horticulture industry have become more familiar with the role of a horticulture therapist in providing them with skilled employees through the AHTA program, Horticulture Hiring Individuals with Disabilities (Davis, 1991). Unfortunately, much misunderstanding of the profession of HT still exists, particularly among horticulturists. The second part of this paper is intended to clarify some of the roles and methods of HT.

Human Issues in Horticulture (HIH)

The broader concepts of HIH are addressed in the American Society for Horticultural Science (ASHS) by the socio-horticulture working group and in the International Society for Horticultural Science (ISHS) by the HIH working group (under formation). The People-Plant Council (PPC) was formed in 1990 to encourage research in this area. To accomplish its goals, it has developed numerous resources available to researchers, students, the industry, and the media. These include books, computerized bibliographies, videotapes, and information on an Internet gopher server (see side bar E for resources available from the PPC). HIH is concerned with the interface between the user of horticultural crops and services and the horticulture industry and professionals (Relf, 1995).


Meeting the needs of special populations is a role to be fulfilled by all members of the horticultural community. Understanding and addressing these needs is an integral part of conducting an extension program, running a retail nursery, hiring new horticultural employees, and many other aspects of horticulture today. Regardless of their areas of study, horticulture students need to be aware of the skills needed and the resources available to work with special populations in order to be effective horticulturists in the twenty-first century.

Horticultural Therapy as a Profession

In order to conduct research, teach courses, or design and implement HT programs, it is important to understand the basic framework and definition of HT, thus sharing a common term for communication. This is made difficult by the fact that the term is used to mean a range of topics, as discussed above. At one end of the range, HT is used to mean any gardening activity that helps anyone in any way. Some people like to use the expression, "If it's horticulture, it's therapy." However, this approach implies that to receive horticultural therapy, all you need to do is plant a seed; and that to be a horticultural therapist, all you need to do is tell someone to plant a seed. This is far from the truth. Although horticulture is good preventative medicine to help overcome the stress and frustrations of daily life, it is an oversimplification to call any use of horticulture, horticultural therapy; just as going for a walk is not the same as physical therapy. The term also is used to talk about community gardening, flower planting and beautification, or vegetables raised by a school child who also happens to have a disability. All of these are oversimplifications and make it difficult to truly understand the nature of HT, why it works, and how to implement it. The remainder of this article is intended to provide the reader with a framework for thinking about HT and developing an understanding of it.

Who Conducts HT Programs
Three groups of individuals are involved in implementing horticultural therapy programs:
  • Professional horticultural therapists who are employed to conduct programs that focus exclusively on horticulture as the treatment method. Horticultural therapists can receive training at several universities and can be registered with AHTA (see article in this issue by Stephen Davis).
  • Allied professionals, including occupational therapists, physical therapists, recreation therapists, etc., who use horticulture as one of the many tools or techniques for treatment of a patient.
  • Volunteers, including members of garden clubs and Cooperative Extension Master Gardeners, who are knowledgeable about horticulture and wish to help others. Volunteers generally are limited in the amount of time that they contribute to a program (two to four hours per week) and the degree of responsibility that they have (usually assisting a professional). However, there are volunteers who work 20 or more hours a week and take most of the responsibility for the program. There is no set system for this, and it depends on the facility, the program, and the volunteer.
Defining Horticultural Therapy

In defining HT as a profession, it is useful to look at the definitions of allied professions, such as physical therapy (PT) and occupational therapy (OT), that use a medical model in their approaches to treatment and receive their salaries based primarily on payments for services from insurance companies, employee health programs, and Medicare/Medicaid. It is to be acknowledged that these professional areas used as models for the development of horticultural therapy are well-established fields recognized by the medical community as integral to treatment, having been in existence for close to 100 years. As HT is approximately 20 years old as a profession recognized by university training, a professional association, and certification, it is still very new and not readily acknowledged among the medical community, particularly insurance companies that must pay for professional services. Often, the horticultural therapist at a facility will be hired under the auspices of the OT department to ensure the payment for services. Horticultural therapists occasionally are employed as activity directors or as recreation therapists when facility budgets do not have the flexibility to include this newer, more specialized treatment area.

Based on material supplied by the American Physical Therapy Association, PT services include identification, prevention, remediation, and rehabilitation of acute or prolonged physical dysfunction or pain, with emphasis on movement dysfunction. PT services staff monitor the extent to which services have met the therapeutic goals relative to initial and all subsequent examinations, as well as the degree to which improvement occurs relative to the identified physical dysfunction or the degree to which pain associated with movement is reduced.

As defined by the American Occupational Therapy Association, registered occupational therapists and certified OT assistants provide services to people whose lives have been disrupted by physical injury or illness, developmental problems, the aging process, or social or psychological difficulties. OT focuses on the active involvement of the patient in specially designed therapeutic tasks and activities to improve function, performance capacity, and the ability to cope with the demands of daily living.

Each of these professions, as well as other allied professions, has three elements in common to their definitions of the professional. They all have clients, goals, and treatment activities. An examination of each of these elements and how they interact for the profession of HT follows:

CLIENTS are individuals who have been diagnosed as having a specific disability or disabilities that can be ameliorated if treated. Clients in HT programs are very diverse and represent all categories of disabilities, including, but not limited to:
  • Psychiatric - Historically the first recorded area to utilize treatment through gardening, this remains one of the major areas in which horticultural therapists work in private and public hospitals and out-patient treatment facilities (Palamuso, 1985; Neuberger, 1991; Kobren, 1991; Liberman, 1992; Schwebel, 1993; Strauss, 1994; Diethelm, 1994).
  • Geriatric - Among the ill elderly, such as those in adult day-care centers, nursing homes, Alzheimer's programs, and others, horticulture is proving to have a calming and therapeutic effect, resulting in a significant increase in its utilization in recent years (Mattson and Hilbert, 1976; Hill and Relf, 1982; Ebel, 1991; Mooney and Nicell, 1992; Roemer, 1994; Mooney and Milstein, 1994; Hoover, 1994; Kaplan, 1994).
  • Mental disabilities - This including developmental disabilities, mental retardation, and brain injury - This is one of the principle areas of involvement for horticultural therapists. With programs in public and private schools, vocational rehabilitation centers, sheltered workshops, and residential facilities, much of the work is directed toward employment of the clients (Airhart et al, 1987; DeHart-Bennett and Relf, 1990; Dobbs and Relf, 1990; Schleien et al, 1991; Cecchettini and Goldman, 1994).
  • Physical disabilities - Patients with strokes, paralyzing injuries, and a multitude of similar diagnoses are being treated in HT programs in many locations around the United States (Bales, 1995).
  • Sensory impairments - Vocational and recreational programs for visually and hearing impaired persons utilize horticultural activities as part of their rehabilitation. However, "gardens for the blind" are recognized as stereotypical and undesirable. Emphasis is placed on gaining skills for daily living (Perkins School for the Blind, 1993; Craig, 1994).
  • Substance abuse - Individuals who abuse alcohol, drugs, and even food have responded to horticultural therapy at certain stages in their treatment (Cornille et al, 1987; Hewson, 1994).
  • Social deviation - Both adults and children who are mal-adapted to society norms and commit crimes that place them in prisons or detention centers have been shown to benefit from horticultural therapy (McGinnis, 1989; Pruyne, 1994; Flagler, 1993; McCombe- Spafford, 1994; Rice and Remy, 1994; Whittlesey, 1994).
DEFINED TREATMENT GOALS are diverse and depend on the diagnosis of the individual and the treatment facility where the program is being conducted. There are two types of treatment goals that must be reconciled: facility treatment goal and client treatment goal. Depending on various factors, including the stage of the disability being addressed and the prognosis, an individual could be in any one of several different treatment facilities with different goals. These facility treatment goals include, but are not limited to: vocational rehabilitation and placement, rehabilitation and return to the community at reduced functioning level, maintenance of functioning level without institutionalization, sheltered or supported employment, and delayed progress of disability. Zandstra (1987, 1988) described individualized treatment goals as part of the total treatment plan that is developed cooperatively with the client and addressed specific needs of that individual. The individualized treatment goal is achieved through a series of treatment objectives that are clearly attainable and measurable. Each treatment objective is written to include:
  • the desired behavior or response
  • the circumstances under which that behavior will occur
  • and the minimum acceptable performance of the behavior
By establishing treatment goals and objectives, it is possible to determine the progress that the client is making in treatment and determine when the patient has derived all the benefit anticipated from a treatment program. This type of documentation increasingly is being required as justification for payment of treatment procedures by insurance companies or government reimbursement agencies.

In reality, due to limited staff, it is impossible to individualize the treatment goals and objectives to the desirable degree discussed. Standardized client treatment goals are used to apply to all the patients in the program with individual progress records being kept.

In addition to facility treatment goals and individualized treatment goals, many HT programs have unwritten goals they are expected to achieve. These generally have less to do with client treatment than with funding or prestige; for example, the HT program is often the most aesthetically pleasing portion of a facility and, therefore, expected to host all visitors despite any impact it may have on the treatment program. Or the products or services that are a by-product of the treatment of a client (i.e., pot plants, vegetables, grounds maintenance services) have economic value and are expected to contribute significantly to the budget of the program. These goals must be integrated into the overall program goals if success is to be achieved.

TREATMENT ACTIVITIES must focus on the cultivation of living plants if the program is truly to be horticultural therapy. Occasional activities may include arts and crafts, field trips, reading, etc., but ultimately, a major therapeutic aspect of HT is the benefit to be derived from nurturing plants; therefore, living plants are essential. Beyond that, the type of horticultural activity should be adjusted to meet the abilities and needs of the client. Specific considerations include:
  • The activity should be the smallest, simplest one available to achieve the desired goal, thus benefitting the most clientele.
  • The therapeutic aspect of the activity is the process itself, not the finished product.
  • Clients who are not participating actively in a specific project, but passively watching (even from their windows), will derive some psychological and physiological benefit from the plants and should be encouraged to continue their observations until they are ready to participate.
Examples of horticulture treatment activities vary from greenhouse crop production to learning to make terrariums and bonsai, from harvesting flowers to dried flower arranging, and from pulling weeds to transplanting trees. Because of the diverse clientele, any horticultural activity could potentially be part of a successful HT program, if appropriately modified to meet the abilities and needs of the client. However, high among the horticultural activities that have long been seen as very motivational are potting plants, plant propagation, and flower arranging (Relf (Hefley), 1973; Relf, 1978).

HT is part of an overall treatment plan, and the people conducting HT programs work closely with all other members of the treatment facility to reach the goals. For other professionals (such as occupational, physical, or recreational therapists) using horticulture as one of their treatment activities, the goals of horticulture will be integrated into the individualized treatment goals of the patient in a similar manner.

For volunteers working with patients in HT, the goals are much more generalized, and they are not requested to maintain records in the same way as professionals. The generalized goals of volunteers in horticultural therapy include helping clients learn to have fun and laugh again, helping clients understand that they are still valuable and people from their community still care about them, helping clients improve physically by getting the exercise of gardening, or helping elderly persons improve mentally by talking about childhood memories of gardening to someone who truly wants to listen. It is essential that professionals in the field of HT develop the skills to work with volunteers.

Literature cited

Acknowledgments: Portions of this paper are from presentations given in Japan in 1994 at Osaka and Tokyo: "Planning and conducting horticultural therapy programs for different populations," Japan Greenery Research and Development Center Horticulture Therapy Workshop, Tokyo, Japan; and "Professional development in horticultural therapy," Heartful Park International Symposium '94, Osaka, Japan.
* Extension specialist, Consumer Horticulture, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0327.
** Graduate research assisant, Department of Horticulture, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0327.