Introducing PHS Digital Classroom
online garden learning series

Pacific Horticulture Society’s FREE online learning series to connect gardeners with some of the most intriguing horticultural and environmental issues of our time. Do you want to begin “gardening like the Earth depends on it”?  Tuning into these conversations is a great way to start.  

Questions or Comments? Email


Gardeners as Superheroes

With Pamela Berstler, PHS’s Executive Director, and CEO of G3, Green Gardens Group
Many of us garden for a love of plants, beauty, or to soothe our psyches, but emerging science on the the importance of healthy soil and biodiversity – goals we gardeners strive for –  transforms our solitary garden practice into meaningful and necessary action to combat climate change and heal the planet. Discover how we become true gardening superheroes by following the four steps of the “Watershed Approach.”  Note that internet connectivity issues make the first few minutes of the video choppy; this resolves at 9:00.


How Much Compost is Enough?

With Calla Rose Ostrander, Marin Carbon Project partner and environmental strategic advisor
Applying compost to degraded soils benefits our gardens by sparking a microbial revolution that holds more water in dry times and encourages plant growth. Learn what up-to-date science is saying about carbon sequestration in landscapes and think through the “Goldilocks Question” of how much compost is just right for our gardens.


Insights Into the Wood Wide Web

With Suzanne Simard Lab University of British Columbia’s Faculty of Forestry PhD candidates, Allen Laroque and Katie McMahen
Below the soil surface plants are carrying on complex interactions with each other and benefitting from the redistribution of resources across a vast fungal network. These researchers are exploring complex symbiotic relationships between trees and mycorrhizal networks and ways in which the forest responds to degradation by participating in the rehabilitation and growth of the soil microbiome. Gardeners learn how to help their landscapes tap into the wood wide web.


Plants for the Wildland Interface

With Dr. Alan Shay, Instructor and Site Manager, Oregon State University’s Oak Creek Center for Urban Horticulture and Neil Bell, Community Horticulturalist, Oregon State University Extension Service
As the Pacific Northwest’s weather continues to more closely align with drier Mediterranean climate zones, gardeners must begin shifting their process — from plant selection and garden design to construction and maintenance — in order to ensure successful adaptation of our gardens and continued biodiversity of the region. Learn the best plants and sustainable horticultural solutions for the Pacific Northwest. Applicable to residential gardens everywhere, whether currently experiencing drought or planning for the future.


Why Hortis Should Care About Biodiversity

With Isaac Brown , Landscape Architect, Biodiversity Project Coordinator for LA Sanitation and Environment Regulatory Affairs Division
Biodiversity hot spots throughout the Pacific region represent the variety of flora, fauna, and ecosystems that help maintain the balance of nature and sustain cities. Urban biodiversity includes urban forests and gardens, and provide many ecosystem services that enhance the community resilience to climate change. Habitat loss, invasive species, development, imperviousness and high population growth all contribute to diminishing biodiversity. Learn more about how biodiversity is measured, mapped, and tracked so that landscapes may be preserved, where appropriate, or re-imagined to ensure the greatest possible amount of biodiversity.


This program was made possible thanks to the generous contributions of our donors and a supporting grant from the Pendleton & Elisabeth Carey Miller Charitable Foundation.