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Community Ecology Institute Purchases Jim and Peggy Duke’s ‘Green Farmacy Garden’

By Connor Yearsley

A garden path leading to a gazebo

On December 21, 2022, the winter solstice, the Community Ecology Institute (CEI),1 a nonprofit organization based in Columbia, Maryland, became the new owner of the former property of a prominent botanical couple: renowned ethnobotanist James “Jim” Alan Duke, PhD (1929–2017),2 and Peggy-Ann Kessler Duke (1931–2021),3 a prolific botanical artist.

The 6.08-acre property in Fulton, Maryland, includes a house that was the Duke family residence and an extensive garden, which the Dukes called the “Green Farmacy Garden” (see “The Green Farmacy Garden” sidebar).4,5 It is about 20 miles north of Washington, DC, and about five miles southwest of CEI’s Freetown Farm, an organic farm that teaches people about sustainability, in Columbia.

Jim Duke with his guitar in the garden in October 2006Jim was probably the US government’s leading medicinal plant expert during a decades-long career as an economic botanist at the United States Department of Agriculture, and he authored numerous books on medicinal plants. He and Peggy entered into a financial arrangement with the Maryland University of Integrative Health (MUIH), which assumed ownership of the property in July 2004. Jim and Peggy were able to continue to live on the property and maintain the gardens. When Peggy died in April 2021, MUIH became responsible for maintaining the property and gardens.

However, because most MUIH classes moved online, the university did not have substantial educational use for the property and decided to transfer it to an organization that would ideally and hopefully maintain the garden and continue to make the site open to the public.

An article in the December 2021 issue of the American Botanical Council’s (ABC’s) monthly online newsletter HerbalEGram announced that MUIH was seeking new ownership for the property.6 That article, the fourth-most-clicked HerbalEGram article of 2021, helped inspire CEI to purchase the property.

“In late December 2021, we received a flurry of emails and phone calls asking if we were aware of the need to protect the Green Farmacy Garden,” wrote Jean Silver-Isenstadt, MD, PhD, president of CEI’s board of directors (email, December 5, 2022). “An HerbalEGram article had just run about the property seeking new ownership. People in the area, who knew of CEI’s success protecting the last working farm in Columbia, thought of us as the natural buyers. With our prior awareness of Jim Duke’s influential work, the article and community outreach inspired us to plan an urgent board field trip to explore this unexpected opportunity.

The Green Farmacy Garden

Jim and Peggy Duke, who collected medicinal plants for more than 60 years, purchased the property in 1971. In 1997, they commissioned the transformation of part of the pastureland into the Green Farmacy Garden, a teaching garden that highlights the plants in Jim’s book The Green Pharmacy (Rodale, 1997).

The garden has been a sanctuary for about 300 native and non-native plant species that have been used traditionally and/or researched for medicinal purposes. It has four terraces with 80 plots designated for 80 different medical indications. Plant species that have grown in Terrace One include ashwagandha (Withania somnifera, Solanaceae), pomegranate (Punica granatum, Lythraceae), and saw palmetto (Serenoa repens, Arecaceae), among many others. Terrace Two has included bloodroot (Sanguinaria canadensis, Papaveraceae), kava (Piper methysticum, Piperaceae), and pineapple (Ananas comosus, Bromeliaceae). Terrace Three has included arnica (Arnica montana, Asteraceae), stinging nettle (Urtica dioica, Urticaceae), and yaupon (Ilex vomitoria, Aquifoliaceae). Terrace Four has included chamomile (Matricaria chamomilla, Asteraceae), echinacea (Echinacea spp., Asteraceae), and witch hazel (Hamamelis spp., Hamamelidaceae).

The four-terraced garden has a pond with a waterfall. Another pond is located on the field part of the property. Many plant species grow in the garden, woods, or are tropical and spend the winters in the greenhouse.

The property also includes a barn and shed that can be used for storage, a screened gazebo, shade shelter, a patio off of the lower level with a small fireplace, and a large chimney fireplace at the bottom of the property. Trails lead from the garden area into the woods where medicinal and native plants grow and are bordered by two creeks with bridge crossings. The property is surrounded by stream valleys, a farm field, and a few homes that are barely visible.

Thousands of people have visited and many have been inspired by the property and garden, which are also part of the Botanical Sanctuary Network of the United Plant Savers (UpS).

“CEI’s mission is to cultivate communities where people and nature thrive together — a mission embodied by Jim and Peggy Duke’s life work,” Silver-Isenstadt added. “When our board first toured the Green Farmacy Garden, we saw synergies everywhere. We saw a place that had been lovingly nurtured to help people build closer relationships with the natural world. Everywhere we looked — from the terraced gardens to the open stone hearths, ponds, creeks, and forest paths — we saw devotion, playfulness, expertise, beauty, and deep-rootedness. The Dukes built community globally but also in their own backyard, through teaching, music, art, and joyful outdoor gatherings.”

On May 26, 2022, CEI sent MUIH a letter of intent to purchase the property, and, on September 23, 2022, executed a contract of sale. According to CEI, the main challenges of purchasing the property were the asking price, MUIH’s eagerness to move quickly due to many offers from potential private buyers, and CEI’s need to fundraise for this purchase while also fundraising for its own operations and capital at Freetown Farm, where the organization was renovating an unfinished barn into its Community Engagement Center, an important project for the organization, as it did not have a finished space with plumbing yet.

To CEI’s advantage, its mission and track record aligned with MUIH’s hopes for the future stewardship of the Green Farmacy Garden. Marc Levin, president and CEO of MUIH, wrote: “We had multiple offers from individuals who wanted to live on the property and make the gardens available to the public. We thought it would be best to find a nonprofit organization to be long-term stewards of the gardens and property. We are all very fortunate that CEI was interested and able to buy the property, as the organization will be an outstanding steward. I am also excited to see how CEI expands the benefit to the community over the years by increasing the programming” (email, December 25, 2022).

Howard County, where the property is located, provided half the funding needed for CEI to purchase the property, and the State of Maryland provided the other half, with the aim of protecting the unique botanical gardens and continuing to provide nature-based education that would be widely accessible. The property will be open to the public through pre-registered workshops, tours, volunteer opportunities, and appointments. CEI does not yet have plans to make any changes to the property but said that any future changes will respect the watershed, forest, neighbors, and character of the site.

Silver-Isenstadt wrote: “This story feels personally magical for me, as I had the privilege of interviewing Jim Duke in 1988, when I was in college and working as a summer journalism intern with Patuxent Publishing. That interview was one of my first publications, and I could never have imagined the way my work would again intersect so directly with sharing Jim’s knowledge and passions.”

Chiara D’Amore, PhD, CEI’s founder and executive director, wrote: “This opportunity feels wonderfully full-circle for me. In high school, I was interested in becoming an ethnobotanist and so I went to the Green Farmacy Garden to meet with Jim Duke and receive his wisdom. In college and graduate school, that interest drew me into the worlds of environmental science and sustainability education, but I always maintained my love of plants and devoted my doctoral research to questions of why and how to maximize people’s time in nature. So, this re-engagement with ethnobotany and medicinal plants is a joy to me” (email, December 5, 2022).

Lily pads in a small pond

CEI first intends to get to know the property’s gardens and land, including its plants and animals, how the water flows, its sun and shade patterns, and what needs pruning. It will assess the needs of the house, with a focus on energy-efficiency upgrades. The organization wants the property to be welcoming to all and will also focus on safety and accessibility. CEI envisions the gardens becoming better known locally and will strive to cultivate passion for plant sanctuaries and undisturbed woodlands. It also intends to listen to and learn from those who knew and worked with the Dukes, to help honor the family’s legacy.

“Botanical gardens require a great deal of steady care and specialized plant knowledge,” Silver-Isenstadt wrote. “We recognize the ongoing need for gardeners who have expertise in medicinal plants and who are excited to teach and carefully oversee community volunteers. Other challenges relate to the site’s infrastructure. Currently, the gardens’ tropical plants are brought inside to overwinter in a small, unheated greenhouse, which is attached to the house, and in the basement of the house itself. In the future, a larger, heated greenhouse may serve the site better.

“Also, the trees have grown a great deal since 1997, when the Dukes established the terraced beds,” Silver-Isenstadt added. “Current and past gardeners have alerted us that some sun-loving plants now struggle with too much shade. We may need to create new sunny beds and/or prune back trees — management decisions that we will make thoughtfully. And perhaps most obvious and challenging in terms of overall site maintenance: invasive plants that threaten the native flora and habitat. This is a struggle we face throughout the region. Because we do not spray chemicals, this will require a lot of physical labor to keep in check.”

Celia Duke Larsen, Jim and Peggy’s daughter, wrote: “My brother John and I are so happy that CEI will steward our parents’ property well into the future. Our parents were aware that MUIH needed to focus on its online learning curriculum, so we very much appreciate that MUIH dedicated the time and effort to find an excellent organization, CEI, to purchase the Green Farmacy Garden and help continue our parents’ legacies.

“We look forward to helping CEI in any way we can,” Larsen added. “That six-acre property and the home and outbuildings are veryA meadow of buttercups near and dear to both of us, as well as many other people in Howard County and the wider herbal community. We are thrilled that CEI will continue teaching people, in an experiential hands-on way, about the joy of plants and nature in general. We also hope CEI will continue to offer live music in the garden” (email, December 7, 2022).

Helen Lowe Metzman, the former garden director of the Green Farmacy Garden, Duke family friend, and president of the board of directors of the United Plant Savers (UpS, a nonprofit membership organization that educates the public and fosters the conservation of native American medicinal plant species), wrote: “Long before I was aware of CEI’s interest in becoming the new owner of the Green Farmacy Garden, I visited CEI’s Freetown Farm and was deeply impressed with the organization’s commitment to integrating land, agriculture, culture, sustainability, and environmental awareness in an artistic, creative way. After it was announced that new ownership was sought for the Dukes’ property, I was approached by the president of CEI’s board and was pleased with the integrity of her inquiries. As I became more acquainted with CEI and its commitment to preserving the Green Farmacy Garden and Jim and Peggy’s vision for the land, it became clear that CEI was the perfect next owner of the property. I was further astonished that CEI was able to raise funds for the purchase with county and state resources.

A ginkgo tree full of yellow leaves has a gazebo in front

“With CEI as the new owner, the Green Farmacy Garden is, at least for now, preserved from the pressures of urban development and will be able to continue its dedication and commitment to medicinal plant education and awareness,” Metzman added. “I hope that CEI will expand the programs to eventually involve large-scale plant cultivation, build a hoophouse, further develop internship opportunities, incorporate permaculture, perform phytomedicinal research, and encourage multitudes of diverse groups to use the rich resources at the garden. The Green Farmacy Garden is fortunate to have CEI as the new owner, and I believe Jim and Peggy would be elated” (email, December 1, 2022).

ABC Founder and Executive Director Mark Blumenthal said: “I am truly pleased that CEI has purchased Jim and Peggy’s former home and gardens and that it plans to continue the Dukes’ remarkable educational legacy. I will always be grateful that Marc Levin contacted ABC to enlist our support in spreading the news among ABC’s vast network of medicinal plant enthusiasts that the property was available to the appropriate buyer. I appreciate MUIH’s good judgment to ensure stewardship, by an organization like CEI, in ways that Jim and Peggy would have wanted. Jim was a key player in the establishment of ABC, as one of our founders and first members of the ABC Board of Trustees, so it seems fitting that HerbalGram Assistant Editor Connor Yearsley’s article in HerbalEGram helped CEI to emerge as the rightful buyer and steward for the Dukes’ home and gardens.”

To help support the long-term sustainability of the Green Farmacy Garden, CEI established the Green Farmacy Garden Advisory Council,7 which is composed of people who had personal relationships with the Dukes and/or have relevant expertise. The Advisory Council includes Mark Blumenthal, herbalist and MUIH faculty member Bevin Clare, CEI collaborator and former Smithsonian Institution scientist Edwin Gould, Celia Duke Larsen, Helen Lowe Metzman, Duke protégé and US Food and Drug Administration scientist Andrea Ottesen, PhD, and environmentalist and educator David Weeks.

CEI also invites anyone with knowledge or inspiration to share it by emailing The organization will also need public and private support to maintain the gardens, make repairs and improvements to the house, which was built in 1957, and continue educational offerings there. Information about making a financial donation is available at:

Duke Ethnobotanical Archives

The United Plant Savers (UpS) has curated the Duke Ethnobotanical Archives,8 which, according to the organization, is the largest collection of Jim’s prolific writings and Peggy’s botanical artwork, as well as their files, notes, and herbarium specimens. The collection is housed in UpS’ Center for Medicinal Plant Conservation, which is dedicated to Jim and Peggy Duke and is located at the entrance of the 379-acre UpS Sanctuary in Rutland, Ohio. UpS’ goal is to preserve the Dukes’ extensive research in a central location and make it accessible to all.

“The Duke Ethnobotanical Archives is growing,” wrote Susan Leopold, PhD, executive director of UpS (email, December 5, 2022). “UpS recently purchased the Brick House Apothecary in Pomeroy, Ohio, to expand the library’s capacity. This will allow us to have more space to dedicate to the herbarium collection and Jim and Peggy’s slide photography, illustrations, and manuscripts. In addition, the house will have rooms on Airbnb, so visitors have a place to stay while researching at the library and/or visiting the UpS Sanctuary in nearby Rutland. The books have been cataloged and are searchable on the library’s webpage. UpS would like to thank the Maryland University of Integrative Health (MUIH) for donating some of the Dukes’ books. We also are excited to announce that we have received book collections from E. John Staba, a pharmacognosist and professor, and Stephen Buhner, an herbalist and author. Our library is growing, and now we have space for expansion.”

Woven baskets rest on a blanket of fallen yellow ginkgo leaves

Image credits (top to bottom):

All images of the Green Farmacy Garden.

The garden path leading to the gazebo. ©2023 Helen Lowe Metzman
Jim Duke playing his guitar in the garden in October 2006. ©2023 Helen Lowe Metzman
Lily pads in a pond on the property. ©2023 Community Ecology Institute
A meadow full of buttercups (Ranunculus spp., Ranunculaceae). ©2023 Community Ecology Institute
The gazebo stands in front of a large ginkgo (Ginkgo biloba, Ginkgoaceae) tree. ©2023 Helen Lowe Metzman
Gathering fallen ginkgo leaves. ©2023 Community Ecology Institute


  1. Community Ecology Institute. Available at: Accessed January 6, 2023.
  2. Foster S. James A. Duke — A Diverse Life of Botanical Bounty. HerbalGram. 2018;117:44-57. Available at: Accessed January 6, 2023.
  3. Yearsley C. Peggy-Ann Wetmore Kessler Duke: 1931–2021. HerbalGram. 2022;132:76-79. Available at: Accessed January 6, 2023.
  4. The Green Farmacy Garden. Community Ecology Institute website. Available at: Accessed January 6, 2023.
  5. The Green Farmacy Garden. The Green Farmacy Garden website. Available at: Accessed January 6, 2023.
  6. Yearsley C. New Ownership Sought for Jim and Peggy Duke’s Maryland Property and ‘Green Farmacy Garden.’ HerbalEGram. December 2021;18(12). Available at: Accessed January 6, 2023.
  7. Green Farmacy Garden Advisory Council. Community Ecology Institute website. Available at: Accessed January 6, 2023.
  8. Duke Ethnobotanical Archives & Teaching Gardens. United Plant Savers website. Available at: Accessed January 7, 2023.