Teaching Sustainability in Horticulture

Kate Congreves

My Why

Creating a sustainable future is a highly complex problem, one that will require multiple skill sets and competencies. Having access to good education inspires students and builds the skills they will need to effect change for a better, more sustainable future. Providing access and space for students to practise and learn these skill sets is the first step toward equipping the next generation with the capabilities to address the challenges around sustainability.

How can we, as teachers, offer the learning experiences that students require to function in a world that so desperately needs to improve sustainability? I joined the Sustainability Faculty Fellows (SFF) program with the goal of learning what experiences we can offer students and how to do so.

I am a soil scientist and agronomist researching and teaching about sustainable agriculture and horticulture, so I joined the SFF program to learn about the things I can do in my classroom and in collaboration with my colleagues to help our students realize their goals and become changemakers for a more sustainable future.

What I Did in My Course

I teach or co-teach several horticulture and agriculture courses. After spending the summer of 2022 in the SFF program, learning from educational specialists at the Gwenna Moss Centre for Teaching and Learning and from other fellows, I moved into the fall term ready (or not) to practise and apply what I had learned in my courses. I used PLSC 220 – Fundamentals of Horticulture to test and apply new ways of teaching students about the United Nations Sustainable Development Goals (SDGs) and of contextualizing sustainability in the foundations of horticulture.

Learning Outcomes

First, I revised the course syllabus and added learning outcomes that target the sustainability concepts I wanted students to learn. In this introductory course, the most important outcomes for students were to

• identify and differentiate various markets for horticultural crops,
• define vegetable crops and examine their characteristics,
• evaluate the features of sustainable horticulture crop production and linkages to the SDGs, and
• plan a sustainable production scenario and reflect on what makes it sustainable or not.

The last two learning outcomes were new.

Teaching Practices

Having a new syllabus and course assessment structure (see “Assessment Strategies,” below), I focused my attention on reviewing my lecture material, communication, and class activities. I tried to identify places where I could make changes to better apply what I had learned in the SFF program about open and active learning.

To make the course more accessible and open, I selected an open textbook covering horticulture at an introductory level (Red Seal Landscape Horticulturist Identify Plants and Plant Requirements, which was published for a similar horticultural course at Kwantlen Polytechnic University in British Columbia), and supplemented this with selected readings from other open sources, including a chapter on soil health published as part of the new open textbook Digging into Canadian Soils, by the Canadian Society of Soil Science.

As for active learning, I had to really think about what this means and how I could best support it. I ended up changing my “lecture style” to foster more active learning.

Learning Activities

Polls to test knowledge uptake: Instead of dictating concepts for the duration of the lecture period, I tried other approaches. I still lectured, but I also used Poll Everywhere (an online platform that lets you host live polls, surveys, quizzes, etc.) to encourage students to think about the concepts before delving into them. Doing so also allowed me to assess their pre-knowledge and gave me an opportunity to dispel myths. Then, as I taught the concepts, I would periodically pause and use the polls to test their uptake of knowledge. I found this strategy fostered a more open and approachable learning environment, where students weren’t afraid of being wrong, and instead were actively learning the concepts as I taught them.

Classroom discussion to define sustainability: I started a class with the question “How do you define sustainability?” Most students immediately responded with correct but routine answers about environmental integrity, social progress, and economic resources. So, to encourage critical thinking, I challenged them by probing further: “Yes, but what is missing in your definition?” After waiting out the uncomfortable silence, this prompted a thoughtful classroom discussion. Through this dialogue, students learned about the “5Ps” of sustainability (People, Planet, Prosperity, Peace, Partnership) and were introduced to the SDGs.

Small group activities: As another strategy aimed at active learning, I created short activities for each class and encouraged small groups to work on and complete the activities together, which was followed by class discussions and sharing. The activities were different each time. Some required students to review

• a table from a publication (like an open report from the Intergovernmental Panel on Climate Change, or IPCC),
• a website or a resource (like the Canadian Food Inspection Agency website, or a vegetable plant classification table), or
• a short reading (like a scientific short communication or perspective article).

I would give them a guided question to work on as they carried out the activity, and they would work together to come up with answers.

As one example, I asked students to review the SDGs as listed on the United Nations website, identify which ones are related to horticulture, and collectively decide on one that most resonated with them. Each group elected a spokesperson who would explain their selected SDG to the rest of the class and share their reasons for selecting it.

Although these activities were short (ranging from 5 to 10 minutes in length), they helped students actively work with the material, make connections, and practise drawing interpretations and communicating them. They also reduced the risk of students tuning out during the rest of my lecture.

Ocean of Optimism: Another activity that I found useful in prompting a classroom discussion on horticultural sustainability was the “Ocean of Optimism.” This activity is done in three stages: first ask students to deliberate a utopia-like scenario, then conduct a critical analysis of the current barriers, and finally have a discussion on the changes needed to move from the present state to a desirable scenario.

I framed the prompts as follows:

1. Ocean of Optimism: Ideally, what would sustainable food production be like?
2. Lake of Despair: What are the current barriers to developing sustainable food production?
3. River of Change: What factors/initiatives/goals would bring about the required changes?

Exploring aspects of public reports: I believe it is important for students to consider and understand different perspectives, so I used a few activities to draw this out of them. For example, I used snippets of IPCC reports (key tables or figures) to get students to see how a group of diverse experts come to their determinations about climate change and impacts. In the reports, conclusions are supported with qualifiers like high, medium, and low relating to expert confidence or consensus, and the direction or magnitude of the impact is often reported using scales. The intention was for students to begin to understand that different perspectives are key for the development of robust systems thinking and problem-solving skills, and that together, students can draw more informed understandings of our world.

Experiential and place-based learning: In the SFF program, we spent time reflecting on experiential learning and thinking about the significance of place-based learning. I believe my course, PLSC 220, was already doing a great job supporting experiential and place-based learning, largely because of the work of other course designers before me, as well as other instructors.

Each week, during our three-hour lab period, students board a bus and are brought to a local commercial horticultural operation (a farm, nursery, greenhouse, market, food bank, warehouse, processor, or innovator). The students hear from the owners and operators and experience the space and activities taking place in these operations. For the fall of 2022, we added new stops, including a trip to Wanuskewin (Indigenous cultural complex and National Historic Site near Saskatoon), where students could learn about native plants and horticultural practices and hear directly from experts on staff. The goal was for students to learn about these plants in an intentional and relevant way.

To help students get the most from the field trip experiences, we gave them their reflective essay assignment beforehand, and we guided them on how to reflect. We used three questions to get them thinking:

1. What did you learn on the field trip? (Provide at least one specific example per location.)
2. Why is it important to you?
3. How will you use what you’ve learned? (Consider your job, future classes, higher education, and life in general.)

Guest lecture from upper-year students: I also exposed students to a real-world initiative closer to home when I invited two upper-year students to come and tell us about a student-led sustainability initiative. These were previous students of mine and are members of the Student Horticulture Club, for which I am the faculty advisor. I had worked with these students over the summer of 2022 to revive the rooftop garden at the College of Agriculture and Bioresources (AgBio). I met with them frequently to plan their garden, helped them get resources to implement their plan and grow their crops, and helped them set up a mini-market in the AgBio Atrium to sell their produce to other students and staff (by donation, pay-what-you-can), and subsequently to sell their produce to Marquis cafeteria.

Knowing that these students were leaders, I invited them to share their project with my PLSC 220 class. I helped them prepare their presentation, and I watched with delight as they taught their peers about vegetable crops and their characteristics and markets; how growing a garden on the AgBio rooftop helps improve campus sustainability; and how the garden links to key SDGs. I was amazed and so proud of these students, and my PLSC 220 students were inspired by them, too.

Assessment Strategies

Many of the activities described above also served as formative assessments (whether the students realized this or not) and were meant to give them practice (thinking, discussing, interpreting) before the summative assessment at the end of the section of the course I taught.

After reviewing the original course syllabus and student feedback from previous years and thinking more deeply about the models of authentic assessment that I learned about as part of the SFF program, my co-instructors and I substantially changed the assessment structure for PLSC 220. In prior years, we tested students with two large exams (a midterm and the final) and one small project. The exams were multiple choice and included questions on all topics covered, including our weekly field trips. But this year, we broke things down into smaller chunks:

• Three multiple-choice quizzes focused on lecture content
• A reflective essay to assess engagement and learning from the field trips
• A small project for landscape design of a volunteer’s yard

For my section, I wanted students to demonstrate that they could apply the concepts taught, so I replaced the multiple-choice quizzes with a written proposal (note: this was before ChatGPT was a thing; see “Lessons Learned,” below). Students were asked to describe their ideas for a new on-campus sustainability initiative, incorporating the scientific concepts that I had taught (vegetable production techniques, horticultural markets, and soil health management), and identify/explain linkages to the SDGs.

My Reflections

At the end of my section, one student came up to me and told me they had never taken a class quite like this one before, where, instead of being “lectured at the whole time,” students were challenged by my open-ended questions in class, something this student appreciated. I took this as a sign that they actually had to think, which was my goal. Granted, PLSC 220 is an introductory-level course, so I am sure the student will experience more courses like this as they progress in their degree.

Lessons Learned

Sometimes, I found it challenging to draw the students out to share their thoughts. After emerging from COVID-19, these students did not have a lot of experience with in-person, in-university courses, never mind voicing their thoughts to the entire class. So, I had to back up a bit. I found that technology like Poll Everywhere helped students “voice their thoughts” anonymously and frequently. Once they got used to interacting with me and their classmates via this platform, they started to open up and speak up more in class. Creating an open and approachable environment was key to fostering more active learning.

Some assignments need to be reconsidered and reformulated now that we are in the world of AI writing. I think we need to focus more on the journey of learning (i.e., fostering deep thinking) rather than the deliverable (i.e., producing an essay). How can we better support students to apply new concepts, think critically and reflect on their ideas, and communicate their thoughts well? Although AI may help with the communication part of the puzzle, it doesn’t help with the thinking part. That brings us back to authentic assessment, meaningful learning outcomes, and the linkages between the two.

I had hoped to provide opportunities for students to build the competencies and skill sets necessary for sustainable horticulture, beyond theory and contexts to also include communicating meaningfully, engaging in our intercultural society, nurturing successful relationships, leveraging technology, employing adaptive design and problem-solving, and cultivating resilience. With revised learning outcomes, teaching practices, learning activities, and assessment strategies, I think we moved the needle in the right direction. We provided opportunities for developing these competencies, but mastering the competencies will require more sustained and systemic curriculum and program design.