Morris Arboretum & Gardens Certificate in Ecological Horticulture

By completing this registration, you are confirming your enrollment in the Morris Arboretum & Gardens’ Certificate Program in Ecological Horticulture. To earn the certificate, students must complete all required coursework (10 core courses + 2 elective courses).   

You may take any certificate class without pursuing the Certificate; however, those who are working toward the certificate must register. This registration also gives you early access to enroll in certificate classes before each course is released to the public (priority registration is ONLY for certificate classes).

This is a one-time administrative fee.

$45.00

The Fall 2025 Certificate Program cohort is currently at capacity. This ensures that all registered certificate seekers will have a space in the courses they need to complete the program in a year, if desired. However, all courses in the program are open to the public. 

*If you're interested in beginning your learning journey this fall, you can register for the Certificate Program courses listed below if space is available. If you enroll formally in the Certificate Program when registration opens for the 2026 cohort, your fall participation will count retroactively towards program completion.*

Dr. Cindy Skema, Botanical Scientist, Morris Arboretum & Gardens

Do you hope to install “living systems” or self-sustaining habitats in your garden/landscape designs? To do so, you need to understand the fundamentals of why and how plants evolve and reproduce, as well as how we capitalize on these natural processes to propagate plant materials for our own use. Expand your concept of designing landscapes to include a need to design plants themselves as genetically and evolutionarily unique entities. We will learn what ecotypes are, how they could impact the success of a landscape project, and why plant provenance really matters. You will be introduced to the plant phenotype and learn what underlies it biologically, what plant plasticity is, and how it may show up in your garden. The course format is two in-person lectures. 

This course is open to the public, with priority registration offered to individuals enrolled in Morris Arboretum & Gardens’ Certificate in Ecological Horticulture. Completion of this course counts toward the requirements of the certificate program. This course has been submitted to carry 3 CEUs with LA CES, ISA, PLNA, and the NJ Board of Tree Experts. 

2 Wednesdays, December 3, 10
6:00 – 7:30 pm

Members: $80 | Non-members: $85

LEE ARMILLEI, Principal, Landscape Designer, APLD

Welcome to the world of ecological design, where environment and art intersect. Get your creative juices flowing as you combine design process & design principles with the ecology you’ve learned in prior certificate courses. Students will design a predetermined site to create a beautiful and immersive space, supportive of people and the planet.

This intensive two-day workshop starts with the basics of understanding the client, analyzing the site and drafting plans, and builds as students shape the landscape using design principles and ecological themes. Students will then develop a site-specific plant palette and apply it to foundation plantings, natural areas, and the spaces in between. Through a combination of lecture, studio-time, and homework, students will gain real time practice and feedback, learning to make informed decisions in ecological design. Although the class will be working on a predetermined site, each design is sure to be unique!

This course is open to the public; with priority registration offered to individuals enrolled in Morris Arboretum & Gardens’ Certificate in Ecological Horticulture.  Completion of this course counts toward the requirements of the certificate program. This course has been submitted to carry 10 CEUs with LA CES, ISA, PLNA, and the New Jersey Board of Tree Experts. 

2 Fridays, January 23, 30
10:00 am – 3:30 pm

Members: $250 | Non-members: $260

Eloise Gayer, Horticulturist, Morris Arboretum & Gardens

Gardeners and land stewards are uniquely placed to combat our planet’s biodiversity crisis by gardening with a sensitivity to the needs of wildlife. This goal can feel overwhelming given the diverse needs of wildlife communities and the enormity of ecological challenges faced by our remaining natural habitat. This course will begin by offering an overview of these challenges, how they might be addressed in a home landscape, and discuss ecological concepts that underpin wildlife gardening, including forest succession, habitat types (edge, canopy, understory, etc.) and habitat heterogeneity. This foundation will inform the practical aspects of the class, which will focus on horticultural techniques that support and encourage wildlife and their application in a variety of garden spaces. We will also zoom in on specific wildlife groups – birds, mammals, reptiles, amphibians, and insects – and discuss ways to manage landscapes with these wildlife groups in mind. 

The lecture component will be held online, and two field components will be held in person, one at the Morris Arboretum & Gardens, and the other at a different regional natural area. These field components will include design exercises to help the participant consider how they might adapt an outdoor space to maximize wildlife benefits and will explore examples of successful management for wildlife in existing gardens.

This course is open to the public, with priority registration offered to individuals enrolled in Morris Arboretum & Gardens’ Certificate Program in Ecological Horticulture. Completion of this course counts towards the CORE requirements of the Certificate Program. This three-part program has been submitted to carry 9 CEUs.

Wednesday, March 25 (ONLINE)
6:00 PM – 9:00 PM

Friday, March 27 (Field day)
1:00 PM – 4:00 PM

Friday, April 3 (Field day)
1:00 PM – 4:00 PM 

Members: $210  |  Non-members: $225

Allison Houghton, Ecological Consultant; Educator

In this course we explore ecological approaches to common pest and disease problems in landscapes. When (and if) problems do arise, they are often indicators of stress or imbalances in the system. Thinking of pests, weeds, and diseases as indicators (even “allies”!) can give us valuable insights into how to return to an overall state of health and resilience. This course encourages students to build their capacity to read landscapes deeply and develop a stewardship approach to land management. We will cover key concepts like life cycles of pests and diseases, what weeds tell us, and how to recognize early signs of trouble as well as strategic intervention points.

Throughout the course, you will learn how to assess environmental conditions, identify stress factors, and choose the most effective solutions for your needs, whether they involve simple interventions or more complex approaches like integrated pest management (IPM). A key component of the course is building the confidence to evaluate the right strategy for your landscape, understanding the range of options available that offer effective, safe and strategic support for a more resilient landscape. We will also discuss strategies for dealing with weeds and animal pests as well as ways to evaluate overall plant health and susceptibility to stress. Ultimately, this course seeks to empower you to engage more deeply in land stewardship, giving you the tools to make decisions that support the long-term ecological health of your landscape.

This course is open to the public, with priority registration offered to individuals enrolled in Morris Arboretum & Gardens’ Certificate Program in Ecological Horticulture. Completion of this course counts towards the CORE requirements of the Certificate Program. This two-part program has been submitted to carry 6 CEUs. 

Wednesday, April 8 (ONLINE)
7:00 pm—9:00 pm

Friday, April 17 (Field day)
9:00 am—2:00 pm

Members: $165 | Non-members: $175

Book Recommendation: 
The Organic Gardener’s Handbook of Natural Pest and Disease Control: A Complete Guide to Maintaining a Healthy Garden and Yard the Earth Friendly Way. Edited by Fern Marshall Bradley, Barbara W. Ellis, and Deborah L. Martin. 2009.

Rebecca Dragonetti, Landscape Designer, Nursery Manager at Refugia Design

In this class we’ll find inspiration in the layered structure of natural plant communities and learn from ecology-based models to select native plants based on competitiveness and response to stress in the landscape. We’ll explore related planting design theories put forth by Nigel Dunnett, Thomas Rainer, & Claudia West. These theories will help us learn how to structure plant lists to achieve our desired outcomes, provide more habitat, and require less inputs than traditional landscape models.

We’ll review specific plant lists related to sustainable garden elements including rain gardens, groundcovers, erosion control, and lawn alternatives, in conjunction with observation of plant communities in the fields. We'll also touch on resources for learning about high performing plants in the trade & how to assess plants at the time of purchase.

This three-part class includes two 1.5 hour in-person lectures, and one 3-hour lecture + field day. All sessions will be held in person at the Morris. This course is open to the public, with priority registration offered to individuals enrolled in Morris Arboretum & Gardens’ Certificate Program in Ecological Horticulture. Completion of this course counts towards the CORE requirements of the Certificate Program.  This three-part program has been submitted to carry 9 CEUs.

Wednesday, April 22
5:00 PM – 6:30 PM

Wednesday, April 29
5:00 PM – 6:30 PM

Saturday, May 2
1:00 PM – 4:00 PM 

Members: $210 | Non-members: $225

Christopher Roddick, ISA Certified Arborist, NOFA AOLCP 

Modern arboriculture recognizes trees as the center of tree-based ecosystem and yet, in practice, we all too often manage trees as isolated organisms. This workshop will introduce you to Ecological Arboriculture, a holistic approach to caring for trees, woody plants, and landscapes, that considers trees as habitat, food sources, and ecosystem engineers. Planting strategies, species selection, and other arboriculture practices can be adapted to increase biodiversity and functionality in the landscape, while still making beautiful spaces.  

Christopher Roddick spent 30 years as the Head Arborist and Foreman of Grounds at the Brooklyn Botanic Garden. Now he moved to southern New England to start Sweet Birch Land & Tree, an arboricultural consultancy and practice. By looking at trees as tree-based ecosystems, Chris follows a holistic approach to caring for trees and land called Conservation Arboriculture. Chris is an ISA Certified Arborist and a NOFA AOLCP. He is the author of the Tree Care Primer, a guide to care for young, mature, and veteran trees.
This class will meet in the Welcome Center at the Morris Arboretum & Gardens. After a morning of learning indoors, we will move into the gardens for an afternoon of learning outdoors. Dress for the weather. 

This course is open to the public, with priority registration offered to individuals enrolled in Morris Arboretum & Gardens’ Certificate Program in Ecological Horticulture. Completion of this course counts towards the CORE requirements of the Certificate Program. This class has been submitted to carry 5.5 CEUs.

Thursday, April 23
9:30 AM – 3:30 PM

Members: $160 | Non-members: $165  

Mallory Sustick, Landscape Stewardship Manager, Refugia Design

Traditional horticulture often employs a cycle of seasonal tasks to maintain designed spaces, such as mulching, fertilizing, pruning and cutbacks. These practices have long been adopted and applied as the norm for many home gardeners with the intention of keeping gardens looking the same year after year. Gardens are not innately static spaces and are composed of many living things, all of which are dynamic and interconnected. Approaching garden management through an ecological lens requires us to position ourselves in relation to the spaces we’re caring for, as opposed to separate from them.

This course will explore the principles and practices of responsibly stewarding different garden types, prioritizing natural resources and ecosystems to ensure their long-term health and resiliency. We’ll compare and discuss different methods and materials that aim to support functional and delicate ecosystems in the garden. Through a combination of in-class and field-based learning, you’ll gain hands-on experience on how to tread lightly and take cues from nature when managing a designed landscape.

This course is open to the public, with priority registration offered to individuals enrolled in Morris Arboretum & Gardens’ Certificate Program in Ecological Horticulture. Completion of this course counts towards the CORE  requirements of the Certificate Program.  This three-part program has been submitted to carry 8 CEUs.

Saturday, May 9 (ONLINE)
9:00 AM—11:00 AM

Friday, May 15 (Field day)
9:00 AM—12:00 PM

Friday, May 22 (Field day)
9:00 AM—12:00 PM

Members: $195 | Non-members: $210

Michelle Detwiler, Ecological Landscape Designer, Owner Wild About Native Plants, Sustainable Landscape Certified

Get to know your local plant communities! Join us for an introduction to the diversity of native trees, shrubs, and perennials at home in Southeastern Pennsylvania. Explore ecoregions to better understand locally-evolved plant species in their natural habitats, and learn about the influences of geography, climate, weather, geology, hydrology, disturbance, wildlife, and land use history on ecosystems. 

Learn to recognize individual species and the site conditions they prefer. This knowledge will help you appreciate, protect, and restore native plant communities, and begin to build your knowledge of local flora as a foundation for thoughtfully reintroducing native plantings into the built environment.

This course includes two 2-hour lectures and two 2-hour guided field sessions to practice identification of representative native plant species and to understand the site conditions where they grow. This course is open to the public, with priority registration offered to individuals enrolled in Morris Arboretum & Gardens’ Certificate Program in Ecological Horticulture. Completion of this course counts towards the CORE  requirements of the Certificate Program. This course has been submitted for 8 ISA, LA CES, and PLNA CEUs. 

Allison Houghton, Ecological Consultant, Educator

Understanding our soils gives us incredible agency in a garden or landscape. In this course we will cover the basics of how to recognize, grow, and support living and resilient soils. We will explore what soil is, the major components and properties of an “ideal” soil and how to actively manage for excellent soil health. You will learn the chemical properties of soil, major and minor nutrients, how to read a soil test, and ways to recognize common deficiencies in plants and in the landscape as a whole. We will address common soil challenges like compacted, degraded and polluted soil as well as strategies for what to do when problems arise. Just as important as the chemical and physical properties of soil, we will explore the incredible role of soil biology in plant health, how you can work with it, add to it, and recognize increased plant health over time.

Throughout the course participants will gain simple hands-on strategies for working with living soils and how to track progress along the way. We will discuss soil testing with a local soil testing laboratory as well as simple home measures to quickly evaluate soil health such as texture, water infiltration, topsoil depth, hardness, aggregate stability and how to read your weeds to track changes over time. Soil is like the living skin of our planet, and soil builders are needed as never before. This course will equip you with the tools and knowledge that absolutely anyone can learn to become a soil steward and work alongside this amazing underground world at our feet.

This course includes one 3-hour lecture (online) and one 5-hour field component at the Morris.  This course is open to the public, with priority registration offered to individuals enrolled in Morris Arboretum & Gardens’ Certificate Program in Ecological Horticulture. Completion of this course counts towards the CORE  requirements of the Certificate Program.  This course has been submitted for 8 ISA, LA CES, and PLNA CEUs. 

Dr. Cindy Skema, Botanical Scientist, Morris Arboretum & Gardens

Join us for an introduction to plant form that will cover the basics of the repeating modular units of growth, both sterile and reproductive, that form the plant body. Students will learn how to recognize different structures of the plant to aid in their understanding of what plants are and how to identify them. We will cover the key topics in plant form: leaf arrangement, leaf complexity, underground parts, as well as floral and fruit structure and diversity. The course format is an in-person lecture followed by a hands-on lab session to dissect fresh material and test our newly acquired knowledge with observations of plants in real time.

This course is open to the public, with priority registration offered to individuals enrolled in Morris Arboretum & Gardens’ Certificate Program in Ecological Horticulture. Completion of this course counts towards the CORE requirements of the Certificate Program. This course has been submitted for 3 CEUs with LA CES, ISA, PLNA, and the NJ Board of Tree Experts.