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Healing Plants: Medicine across Time and Cultures, an Outdoor Exhibition and Medicine Trunk

Contributed by Elayna Singer, Morris Arboretum, 9414 Meadowbrook Avenue, Philadelphia, Pennsylvania 19118, USA.


The Morris Arboretum has created an outdoor exhibition and a related hands-on curriculum which explore the cross-cultural, historical and world-wide use of medicinal plants. Exhibition panels introduce Arboretum visitors to the diversity of medicinal plants and their traditional use by African-Americans, Asians, colonial settlers and Native Americans. The Medicine Trunk contains six lessons and was created for use in grades 2-5. Children discover the similarities and differences between medicinal plants and the people who use them, with materials such as a map of the world, cards illustrated with medicinal plants, smell jars and plant presses. This interactive curriculum, for use in the schools, is complemented with a visit to the Arboretum. During their Healing Plants tour children search for live medicinal plants, pretend they are healers, and ‘prepare’ herbal remedies.

Below is an overview of the largest outdoor exhibition ever presented at the Morris Arboretum of the University of Pennsylvania, entitled “Healing Plants: Medicine across Time and Cultures”. Also included is an introduction to the Medicine Trunk curriculum and the Healing Plants tour for children, in addition to a compendium of Healing Plants programs for adults.

Healing Plants

The Healing Plants project has been six years in the making. It began on July 5 1989 when a specially created Arboretum committee met to outline plans for an international symposium on ‘Plants as Medicine’, in collaboration with the World Health Organization. The symposium met in Philadelphia in 1993 and for the event we created a preliminary outdoor exhibition: a tour of medicinal trees at the Arboretum. Our modest self-guided tour greatly appealed to our visitors, and this persuaded the staff to consider expansion.

We approached the National Endowment for the Humanities (NEH), a Federal agency, with our idea for a major outdoor exhibition on medicinal plants. NEH was impressed by what we had accomplished and the ideas we presented. Subsequently in December of 1995 the Morris Arboretum was awarded $250,000 from NEH to create the Healing Plants outdoor exhibition and related programs.

The Healing Plants program has been a unique endeavor for the Arboretum staff in several ways. Not only is the outdoor exhibition the most significant interpretive effort at the Arboretum to date, it is also the first educational project that has been elevated to program status. In other words, the program was not developed in isolation by one person in one department. Instead, as project manager, I worked closely with staff from every department of the Arboretum including Horticulture, Development, the Center for Urban Forestry, Business, Botany, Communications, Physical Facilities, and Education. We met as a committee every two to three months to keep everyone informed of progress and to solicit input, and in between the committee meetings I worked individually with staff from different departments to move the program forward. The interdepartmental involvement in program development and implementation has cultivated a sense of ownership for the Healing Plants exhibition among the Arboretum staff. It has also increased the prominence of Education, with a capital "E", since staff from all departments have contributed in some way to this major educational program at the Arboretum.

I believe that over the past year and a half, staff have increased their understanding of the educator's perspective in exhibition development and how it relates to their part in the process. I have seen staff become less resistant and more accepting of the rationale for approaching their work in a manner that facilitates reaching the set educational goals and objectives of the Healing Plants program. For example, the horticultural staff designed medicinal plant displays so that labels describing the medicinal uses of plants were easy to view. It was a new feat for the Arboretum to have educational goals dictate garden design.

Healing Plants – an Evaluation and Prototyping

This program has been full of firsts for the Arboretum. In addition to it being our first major interdepartmental interpretive program, it was the first time that substantial resources were committed to evaluating prototypes before the permanent features were in place. It was also the first opportunity we had to develop a hands-on, interactive school curriculum with a complementary Arboretum tour for children.

In the fall of 1995 and the spring of 1996 staff and volunteers conducted evaluations of the outdoor exhibition, the Medicine Trunk and the children's tour. Staff involvement in the evaluation process greatly contributed to their increased ability to quote "see" things through the eyes of an educator. They learned evaluation techniques and were introduced to museum standards for developing interpretive panels. Despite some initial resistance, Physical Facilities staff supported the need to create prototype exhibit panels. They came to appreciate the value of crafting mock-up stations to actual size in the garden in order to critique possible designs for their aesthetic and functional qualities. Through evaluation we also learned a great deal about the content or information presented on our mock-up storyboards.

Evaluators asked visitors a series of questions to see if the intended messages were clearly presented and of interest. As a result of visitors’ suggestions, some exhibition panels were completely changed, while others had only subtle changes made. Over and over again we received requests to include more information about current scientific research and the modern-day uses of medicinal plants. In our initial storyline developments we shied away from presenting much about the current use of medicinal plants, for fear of liability suits and concerns about accountability. Instead we presented more about the historic or past uses of medicinal plants.

As a result of our evaluation, all exhibition panels now highlight the past and present uses of medicinal plants. To protect ourselves we include a disclaimer or word of caution on every exhibition panel stating that the exhibition aims to provide information and stimulate awareness of plants as medicine. The information is primarily for reference and education. It is not intended to be used for self-diagnosis or self-medication. We also recommend that the diagnosis and treatment illness should come under the direction of a qualified health-care professional.

Themes and Exhibition Areas

Three major themes are presented throughout the exhibition and related programs:

  • the diversity of cultural practices and how this governs how medicinal plants are used in specific cultures and in different historical periods
  • the significance of botanic gardens and arboreta in Western scientific tradition and the important role they have played in plant medicine for several centuries
  • the ethical considerations related to the preservation, conservation and stewardship of the world's resources.

Six garden areas have become outdoor mini-galleries with large exhibition panels. Below are some of the stories told in the exhibition:

Since the rose garden at the Morris Arboretum is patterned after the design of other university gardens, it is a perfect place for us to learn about the some of the first university botanic gardens such as Padua and Oxford, which grew medicinal plants for use in their medical schools. Here visitors also learn about a medicinal tea made from the flowers of the apothecary's rose, which is approved in Germany for the treatment of mild inflammations of the mouth and throat. Visitors also discover that dog-rose hips are valued for their vitamin C.

Near the herb garden visitors learn about the European tradition of growing medicinal herbs in cultivated garden areas. They see an example of a medieval herb garden and historic Philadelphia herb gardens such as the one at the College of Physicians of Philadelphia, which grows medicinal plants that were used in the 18th century.

Another station explores how botanic gardens, pharmaceutical companies, and other research organizations are working together to discover and cultivate medicinal plants. Visitors learn that only a small percentage of the world's flora has been tested for their medicinal value, but even this sample has already produced treatments for cancer, glaucoma, and other major diseases. The botanist Jay Walker of the Institute of Economic Botany of the New York Botanical Garden can be viewed collecting the pods of the San Juan tree, which are then shipped to the National Cancer Institute to be screened for their usefulness in treating cancer and AIDS. The Morris Arboretum, in collaboration with the international pharmaceutical company SmithKline Beecham, conducted research during 1988-1995 on Camptotheca acuminata, a valuable plant in the fight against cancer. This Chinese tree contains an anti-tumor compound recently approved by the Food and Drug Administration for treating severe cases of ovarian cancer in women whose cancer does not respond to other forms of treatment. Visitors also learn that weeds and other familiar plants have medicinal uses such as the dandelion, which aids digestion, and the purple coneflower, which soothes cold symptoms.

Multicultural Aspects

The multicultural emphasis of the Healing Plants exhibition is concentrated in three exhibit areas. One station is devoted to African-American herbal traditions. Visitors are introduced to Blanche Epps, a Philadelphia herbalist who specializes in the use of weeds and food herbs for healing. Perhaps to their surprise, visitors also learn that some plants that were used medicinally in the past should no longer be used, such as the sassafras tree, whose root bark was made into a tea to purify blood, for stomach and kidney problems and as a tonic. Today, modern research has shown that the essential oil of sassafras bark is a strong liver toxin and is cancer-causing.

In another station devoted to Native American and colonial plant medicine traditions, visitors see a sample recipe from a colonial remedy book and learn about the treasured medicinal plants that settlers brought with them. They also meet herbalists such as Nora Thompson Dean, a Delaware Indian, who they see sprinkling herbs over a sacred fire.

In the final exhibit area visitors learn about some of Asia's herbal heritage. The Chinese were the first to discover that using plants to heal depended on the interaction of many different chemicals in plants. The exhibition shows examples of familiar plants in American neighborhoods and botanic gardens which are used as medicine in China. Daylily root is used in China to treat cancer. Chrysanthemums are traditionally used to relieve headaches. Forsythia stems and leaves treat conditions of the heart and lungs. Fosythia seed capsules are used for urinary infections. In Kampo, Japan's traditional plant medicine, prescriptions contain up to thirteen different herbs.

Ancillary Programs

The Healing Plants outdoor exhibition is primarily for adult visitors. Additional Healing Plants programs for adults include two indoor art exhibits. One featured Amazonian photographs by the father of ethnobotany, Dr. Richard Evans Schultes. The second was a print collection of medicinal plants mentioned in Shakespeare. As part of our adult continuing-education program we have offered classes and workshops on various topics related to healing plants. By spring 1997 a catalog and self-guided tour will be produced to complement the outdoor exhibition. Lastly, on October 12 1996, the opening of the outdoor exhibition with a Healing Plants festival will be celebrated. This will be a fun-filled day for the entire family.

The Medicine Trunk

Designing the Healing Plants program for children presented another challenge. Most children think of medicine as something that comes in a bottle, capsule or tube at their local drugstore. The Medicine Trunk was developed for school children in grades two through five, to teach them the cross-cultural, historical, and current uses of medicinal plants. The Medicine Trunk is a box that contains materials and a hands-on interactive curriculum. Prototype Medicine Trunks were developed and tested by teachers and students in the Fall of 1995 and the Spring of 1996. In the “Medicinal Plants in Your Life" lesson, children interview adults to find out what they know about herbal remedies and they examine labels of common medicines which are made from plant compounds. In the "Where do Coughdrops Come From"? lesson students learn how medicinal plants are used all over the world. Here we see sample medicinal plant cards. On the front of each card is a description of how the plant is used medicinally in that continent, and on the back of each card is general information about the continent's climate and the people who live there. Children do some independent research and make posters about medicinal plants that have significant economic importance such as corn, coffee, and cocoa. They then present these to their classmates. In the "Creating a Neighborhood Herbal" lesson students gather and press plants from their school yards or neighborhoods to create a classroom herbal. In both the Medicine Trunk and Healing Plants tour for children at the Arboretum, safety messages and warnings about the dangers of misusing plants or trying to use a plant as medicine without the guidance of an adult are reiterated and reinforced in every lesson and activity.

Healing Plants Children’s Tour

After children have done at least one lesson from the Medicine Trunk, they can visit the Arboretum for a special Healing Plants tour. On the tour children learn more about how people from different cultures use plants as medicine. Mortars and pestles, a kettle and saucepan; these are the tools students use to crush, grind and pretend to steep and boil samples of dried plants to make herbal remedies. In our log cabin volunteer guides pretend they are a colonial healer and ask students to imagine they are their apprentices. Together they "prepare" tea from plantain seeds, a lotion from witch-hazel twigs and leaves, and a tea from dandelion leaves.

A Guide will ask “Where do medicinal plants grow? Did you know that healing plants grow everywhere, even in the grass under our feet"? With a frame in hand, students search the grass for valuable medicinal weeds such as white clover, plantain, oxalis, ground ivy and dandelion. Children are surprised to learn that the familiar yellow dandelion flower, as well as its roots and leaves, have all been used as medicine.

In the Fernery, students search for ferns with medicinal value. At the Arboretum's herb garden, students pretend they are a Native American, African-American or Asian herbalist. Their task is to guess a symptom (e.g. stomach ache, sore throat) acted out by one of the students, and then "prescribe" a plant to cure the patients ills. Colorful cards, with pictures of medicinal plants and description of how to treat certain symptoms, help children discover that, according to different cultural traditions, the same plant sometimes treats different ailments and at other times different plants treat the same ailments. Children read and share information about the plants on their cards, then search for the live plants growing in the garden.

Evaluation and Feedback

The Medicine Trunk and the tour seem to be successful in providing a way for children to begin to reshape their attitudes about medicine AND plants. Teachers have also been pleased with using the prototype Medicine Trunk, because its lessons can be integrated into almost any curriculum, for example: social studies, science, mathematics, and history. The visit to the Arboretum then brings the lessons to life for both student and teacher.

Healing Plants: Medicine Across Time and Cultures is a significant achievement for the Morris Arboretum. As educators we are reaching outside of our department to draw on the expertise of the entire Arboretum staff. As plant scientists we are reaching outside of our own sphere of research to consult with local herbalists and practitioners. And finally as exhibit curators we are continually asking our audience how we can better communicate the layers of culture and science that we have uncovered in the creation of this program.