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The Flower Show

Know to Grow

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Grow Smarter with Monthly Gardening Insights

​​​​​​​Know to Grow is a monthly webinar series that brings gardening knowledge straight to you. Whether you're an experienced grower or just getting started, each session is packed with expert insights and fresh inspiration moderated by PHS Vice President of Horticulture, Andrew Bunting. Join for just $20 per lecture or become a PHS member (starting at $5/month) and attend every session for free!

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Upcoming Lectures

September 10, 2025 at 5:00 pm
Patrick Spero – “Botany and Betrayal: André Michaux, Thomas Jefferson, and the Conspiracy of 1793 with Patrick Spero”
André Michaux was one of the most accomplished scientific explorers of North America before Lewis and Clark, known for his major contributions to botany and horticulture. During his decade-long American sojourn, he established a botanical garden and introduced countless native plants to Europe. Yet Michaux also found himself thrust into the middle of a vast international conspiracy. This fascinating talk blends political intrigue with botany and highlights a little-known chapter where early American horticulture and global ambition intersected.

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October 8, 2025 at 5:00 pm
Dee Hall Goodwin – “The Giving Garden: Cultivating Native Flowers to Transform Your Cutting Garden and Community”
Join us for an inspiring conversation with floral designer and urban flower farmer Dee Hall Goodwin as she shares how growing native flowers can transform your cutting garden and strengthen your community. Learn practical tips for cultivating seasonal blooms that support local ecosystems and combine beauty and purpose in every bouquet.

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November 12, 2025 at 5:00 pm
Andra Nus – “Meet the Pawpaw: A Native Fruit Tree with a Tropical Twist”
Meet the pawpaw! With custard-like fruit that tastes like mango, banana, and melon all in one bite, this native North American tree is a hidden gem grown across USDA Zones 5–8. Join pawpaw grower and expert Andra Nus to learn how to grow, care for, and enjoy this unique fruit tree. You’ll get practical tips on everything from planting to harvesting.

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December 10, 2025 at 5:00 pm
Andrew Conboy – “Everyday Actions for Greener Communities”
Learn about how everyday people can help restore nature in their own backyards, parks, and neighborhoods. From planting native trees to removing invasive species and rallying volunteers, Andrew shares simple, powerful ways to make a real ecological impact in communities, both online and in real life.

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More lectures will be added throughout the year. Become a PHS member or sign up for our newsletter to get future updates.

Past Lectures

A fresh look at the ecological and horticultural roles of non-native plants! Have you ever gotten into a discussion about the “goodness” or “badness” of a non-native plant? How about a lecture on why native-only landscapes are the only correct direction for horticulture to go? Join horticulturist David McKinney for a thoughtful discussion on the value and complexity of non-native plants in our landscapes. While native plants are essential to ecosystem health, many non-native species also provide important benefits including supporting pollinators and offering habitat for wildlife.

Join native plant expert Kevin Zuidervliet as he shares standout choices for home landscapes like snowberry (Symphoricarpos albus), a large shrub with bright white berries, and bladdernut (Staphylea trifolia), a medium sized tree with unique seed pods.


About the Speakers

Andrew Conboy

Presentation: “Everyday Actions for Greener Communities”
Andrew is a local urban forester and ISA-certified arborist who is passionate about trees, native plants, and the natural world. Through his social media platforms and his ecological restoration non-profit, the Community Canopy Project, he hopes to encourage a deeper integration of nature into the spaces where we live, work, and play. His user-friendly content on social media platforms (@Andrew_The_Arborist) aims to educate and inspire people to reconnect with the natural world around them.

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Dee Hall Goodwin

Presentation: “The Giving Garden: Cultivating Native Flowers to Transform Your Cutting Garden and Community"
Dee Hall Goodwin, a Norfolk, Virginia-based floral designer and urban flower farmer, blends eco-consciousness and artistry through locally grown, seasonal blooms. Inspired by her grandmother’s garden in St. Lucia and her childhood in Brooklyn, Dee founded Mermaid City Flowers to celebrate nature’s beauty while supporting community-sourced farming. As the founder of the Tidewater Flower Collective and Black Flower Farmers, Dee champions sustainable practices and diversity in floriculture. Her work has been featured on PBS, and in publications including Black Flora, Garden and Gun, and Country Living, reflecting her dedication to floristry as a blend of art, nature, and heritage.

dee hall goodwin headshot
Dee Hall Goodwin

David McKinney

Presentation: “Looking at Non-Native Plants with Fresh Eyes”
David McKinney is a horticulturist, ecologist, entomologist, and plant physiologist currently working as the curator at the Iowa Arboretum and Gardens where he manages 160 acres of gardens, prairie restoration, and native woodland. Originally from Colorado, he received three degrees in horticulture from Colorado State University while also coordinating extensive perennial trials and demonstration gardens. He is passionate about native plants, and the interactions between plants and wildlife. On top of his curatorial work David is an award-winning writer and speaker, recently receiving the Emerging Perennial Professional Award from the Perennial Plant Association and Kenneth Post Award from the American Society for Horticultural Science.

David McKinney
David McKinney

Andra Nus

Presentation: “Meet the Pawpaw: A Native Fruit Tree with a Tropical Twist”
Andra Nus is the owner of Sleepy Gap Pawpaws, a pawpaw nursery and orchard outside of Asheville, NC. She has three decades of horticultural experience in gardening, garden design, nursery management and plant breeding.

Andra Nus
Andra Nus

Patrick Spero

Presentation: “Botany and Betrayal: André Michaux, Thomas Jefferson, and the Conspiracy of 1793 with Patrick Spero”
Patrick Spero is the Chief Executive Officer of the American Philosophical Society and a scholar of early American history. Dr. Spero is the author of four books on the era of the American Revolution. They are Frontier Country: The Politics of War in Early Pennsylvania (2016), which was named a staff pick by the Philadelphia Inquirer in 2017, Frontier Rebels: The Fight for Independence in the American West, 1765-1776 (2018), winner of the Philadelphia Athenaeum’s Literary Award and a finalist for the Journal of the American Revolution’s best book of the year, The Scientist Turned Spy: Andre Michaux, Thomas Jefferson, and the Kentucky Conspiracy of 1793 (2024), and The Other Presidency: Thomas Jefferson and the American Philosophical Society (2024). He is also co-editor of The American Revolution Reborn: New Perspectives for the 21st Century (2016), a book that one reviewer said “will surely secure a place in the historiographical pantheon.” In recognition of his scholarly and administrative accomplishments, he is an elected member of the Royal Historical Society (2023), the Academy of Arts in Science in Lyon France (2023), the American Philosophical Society (2023), and the American Antiquarian Society (2023).

Patrick Spero
Patrick Spero

Kevin Zuidervliet

Presentation: “Top Native Trees and Shrubs for Your Garden”
Kevin is a 2013 graduate of Susquehanna University with a degree in Student Development in Higher Education. After graduation he traveled to Australia and New Zealand where he worked on organic farms for 6 months. This sparked an interest in gardening and horticulture.  When he returned to the states, he joined AmeriCorps VISTA at Bucknell University where he ran the Lewisburg Community Garden, which is still thriving today. After AmeriCorps, he was accepted into the Professional Horticulture Program at Longwood Gardens. He worked another three years at Longwood Gardens as a Nursery Horticulturalist, growing woody plants. After working at Longwood Kevin joined Octoraro Native Plant Nursery’s team as the Head Propagator in 2021. In January of 2025 Kevin and his wife transitioned into owning Octoraro and he is currently the Owner - Grower there.

Kevin Zuidervliet
Kevin Zuidervliet