Garden Symposium

The second annual Garden Symposium will bring together garden enthusiasts from near and far to hear from some of the most influential and innovative voices in the global gardening community. 

Friday, May 3, 2024

Andalusia Historic House, Gardens & Arboretum (1332-1202 State Road, Bensalem, PA 19020) & The Holt Center (2544 Bristol Pike, Bensalem, PA 19020)


The Garden Symposium begins with a coffee reception and welcome, followed by lectures from four world-renowned horticulturalists and lunch. Thanks to the successful launch of the event in 2023, this portion of the day will take place at The Holt Center to accommodate more attendees.

The Garden Symposium will then continue at Andalusia Historic House, Gardens & Arboretum, where guests can enjoy an afternoon tea, book signings with the speakers, and an opportunity to explore the magnificent 50-acre gardens and grounds located on the banks of the Delaware River.

Participants are encouraged to extend their visit to attend Andalusia’s magnificent Garden Party the next day, Saturday, May 4, tour the many gardens and arboreta that make Greater Philadelphia “America’s Garden Capital,” and explore the beauty of Bucks County.

The Symposium is presented by The Letitia Glenn Biddle Society. All proceeds will go towards funding summer internships in horticulture for aspiring professionals working in the field.  

Thanks to Our 2024 Sponsors

Wendy and Wade McDevitt

June and Hank Smith

Thanks also to our 2024 Patrons:

Kristin & Jamie Biddle | June & Hank Smith

This Year’s Speakers

Troy Scott Smith

Read Bio

Troy Scott Smith

Since 2013, Troy Scott Smith has held the position of Head Gardener at Sissinghurst Castle Garden, a garden held dear in the hearts of millions of garden aficionados as the quintessential model of a romantic 20th-century English country garden. His first encounter with Sissinghurst, however, was working as a gardener over thirty years ago. After just five years, Troy left to work for the National Trust Garden, Bodnant, located in North Wales, where he was responsible for a massive restoration effort over seven years.

Troy arrived back at Sissinghurst in 2013 with the ambitious mission of conserving this world-renowned garden in the manner of its noteworthy creators, Vita Sackville-West and Harold Nicholson. Before starting, Troy studied the distinctiveness of Sissinghurst as well as the characters of Sackville-West and Nicolson—not only their gardening styles, but their philosophy, taste, motives, interests, constraints, and ideas. When Vita first laid eyes on the empty plot, she wrote, “It caught instantly at my heart and my imagination. I fell in love; love at first sight.” Indeed, for Vita gardening was about romance, emotion and intimacy—all qualities that Troy wants to highlight for visitors.

Troy says his mission at Sissinghurst is to garden in a way that recaptures the distinctive qualities of Vita and Harold’s Sissinghurst, and to create “a garden of timeless quality, where flower borders bloom in unorthodox exuberance and roses tumble from the walls in lavish swags. Past, present, and future should all equally co-exist.”

Stefani Bittner

Read Bio

Stefani Bittner

Stefani Bittner is the owner of Homestead Design Collective, a San Francisco Bay Area landscape design firm focused on creating beautiful gardens that provide edible harvests. Stefani is the co-author of The Beautiful Edible Garden (2013), Harvest: Unexpected Projects Using 47 Extraordinary Garden Plants (2017), and The Fragrant Flower Garden (2024), all published by Ten Speed Press.

Stefani’s team offers a unique and sophisticated approach—using both organic farming and fine gardening skills—for people who want help creating aesthetically designed, organic, edible gardens. Homestead provides design, installation, and full-service organic maintenance, harvesting, bee keeping, preserving, floristry, and composting services. Homestead is the design team behind the Test Gardens for Sunset Magazine and the chef focused edible gardens for Robert Mondavi and Prisoner wineries. Her gardens can be found in commercial properties, public spaces, and private residences, and her work has been featured in San Francisco Chronicle, The Wall Street Journal, Los Angeles Times, Vogue, Sunset Magazine, Food & Wine, Time Magazine, Better Homes & Gardens, Modern Farmer, Food52, and

Lucy Hunter

Read Bio

Lucy Hunter

Lucy Hunter is an award-winning landscape designer, based in the rural mountains of North Wales, with over 20 years of experience creating garden spaces for clients at home and abroad. She is a self-taught photographer and fine artist who would describe herself as a ‘restless creative.’

Lucy is passionate about the natural world, flowers, and landscapes in all their guises. She travels the globe, designing gardens, teaching, and encouraging guests in sell-out workshops to take cues from the landscape and nature to inspire their creativity and floral world.

Lucy has published two books under The Flower Hunter, on floral design inspired by the seasons and the landscape. You can find her @lucytheflowerhunter.

Dan Hinkley

Read Bio

Dan Hinkley

Dan Hinkley is a professor, plantsman, nurseryman, garden writer, horticulturalist, and design consultant. Born in North Central Michigan, he currently resides in Washington State, where he serves as director emeritus for Heronswood Nursery, which he founded with his partner Robert Jones in 1987. Heronswood’s offering of rare and unusual plants led him on collecting trips to China, South and Central America, Mexico, New Zealand, South Africa, Nepal, Vietnam, Taiwan, Sikkim, Bhutan, Northeast India, and Myanmar numerous times a year for the past 22 years.

Dan has written for numerous periodicals, including Pacific Horticulture, The American Gardener, Garden Design, The Gardener, Horticulture Magazine, American Nurseryman, Gardens Illustrated, Martha Stewart Living, Fine Gardening, and The English Garden, and has had recurring features in Horticulture Magazine and The Seattle Times. He has appeared as a garden correspondent on Martha Stewart Living, and in 2007 explored the flora of remote mountains in China on PBS’s Nova: The First Flower. Dan has been the recipient of many awards, including the distinguished Veitch Memorial Medal for outstanding contributions to the advancement of the science and practice of horticulture from the Royal Horticultural Society.

Dan currently resides in Indianola, Washington with his husband of 37 years and their two goldendoodles, where he is in the process of realizing the gardens of Windcliff. Among many and varied garden spaces, the project includes an arboretum based entirely on his collection work of three decades, a large greenhouse, a generous potager, and an experimental meadow, all on 6.5 acres of south-facing bluff overlooking the Salish Sea. When not working in the gardens, Dan works as a horticultural consultant with architects and landscape architects on a broad assortment of projects across the globe, including the Amazon Spheres in Seattle and the Kogod Courtyard at the Smithsonian National Portrait Gallery in Washington, D.C.

Schedule of Events

Friday, May 3, 2024

  • 8:00 – 8:45 am: Registration and Coffee Reception at The Holt Center (2544 Bristol Pike, Bensalem, PA)
  • 8:45 am – 2:45 pm: Program with Lunch
  • 3:00 – 5:00 pm: Afternoon tea at Andalusia Historic House, Gardens & Arboretum (1237 State Road, Andalusia, PA), with book signings by the speakers, and an opportunity to stroll the extensive gardens.

The 2024 Symposium is Presented to You by 

The Letitia Glenn Biddle Society.

Billie Bailkin
Kristin Biddle
Amanda Burch
Alison Carabasi
Jenny Rose Carey
Amy Coes

Jane Corrigan
Kim Garno
John Giacomazzi
Pia Halloran
Diana Mason
Wendy Mahoney

Wendy McDevitt
Elizabeth Proctor
Jeannette Smith
June Marshall Smith
Mary Smith
Kathy Spagnola

Eileen Stoveld
Libby Sullivan Trammell
Rebecca Williams
Anne Wilmerding
Judy Xie
Liz Zelov


Images from the 2023 Garden Symposium, with speakers Fergus Garrett, Annie Novak, Frances Palmer & Xa Tollemache


Historic House

Learn More

Enter the Grandeur Of

The Gardens

Learn More

See the Beauty of The


Learn More