Community Greenhouses Grow More Than Food
I spent a spring teaching kids about gardening and passive solar greenhouses—and I learned just as much as they did.
The author (right) and a colleague outside the Passive Solar Roller
This spring, I watched as a mother held her daughter’s hand up the stairs into the community greenhouse in Cochrane, AB, the town where I live. Once inside the tiny house-shaped building, they both looked around, amazed by the beans and tomatoes vining up the walls.
“It reminds me of home,” the mother smiled warmly, referring to her country of origin, Bangladesh. Although the plants were different from what she had grown there, the feeling of lush growth felt comforting. She said she was having a hard time gardening in Alberta, with our strong winds, clay soil, and drastically swinging temperatures. We talked shop, shared ideas for what to grow, and then she held her daughter’s hand down the stairs again.
I spent my spring in this greenhouse working as the educator/coordinator for a local non-profit called Cultivate Cochrane, teaching kids and families just like this about worm poop tea (a natural fertilizer), “armpit pruning” tomatoes (to improve plant health and fruit ripening), and a solar-powered fan that sucks (read on to learn more!). After construction finished, I taught over 600 local youth about gardening and sustainability. They ranged in age from teens down to babies, although the littlest did less “learning,” and more experiencing. When I think about that mother and daughter, I’m grateful to be part of a space that connects our community members to themselves, to one another, and to the food that nourishes us all.
If you’re not familiar, community greenhouses are like community gardens, but enclosed so gardeners can grow food in harsher climates. A notable early Canadian example is in Inuvik, NT, where the community garden society in the arctic town converted a 370 square-metre hockey arena into a greenhouse in the late 1990s. Cochrane’s is only about 12 square metres.
But this community greenhouse isn’t just notable for being tiny. It’s called the Passive Solar Roller, a name that refers to both the way it’s heated, and the wheels on which it gets towed by a team of heroic volunteers from Big Hill Towing to schools (including my son Little Grey Lamb’s) and gathering places like the Boys and Girls Club. But don’t let the “passive” in its name mislead you; like many other community greenhouses, this mobile growing space actively contributes to building connection, sustainability, and resilience in Cochrane.
Although I was already an avid gardener, I didn’t know much about greenhouses before taking on this role. I quickly learned that one reason this greenhouse is special is that it looks like a tiny house for plants. This isn’t simply for the cute design, but to provide effective insulation. Most conventional greenhouses have a clear material on all sides. They let in tonnes of light, but need a heater to offset the heat lost from poor insulation. Some also use external energy for fans to get rid of extra heat. But in a passive solar setup, the building collects and retains solar energy without any intermediary devices to capture, store, vent, or convert it.
In passive solar design, materials are intentionally chosen for how they impact the light, temperature, and humidity inside the greenhouse. R-values (a measure of insulation effectiveness), roof angles, and heat transfer qualities of wall materials were all meticulously researched by board members and local sustainable design company OnGrowing Works in the hopes of creating a three or four season growing space. Although the goal is to have fresh local veggies in an Alberta January, this greenhouse is an experiment, so its winter performance is still unknown. The Roller also features a single solar panel (which a purely passive system wouldn’t) to power a “climate battery”: a fan that sucks the hot air in the greenhouse down into the soil bed and forces it out as cooler air.
There are so many cool things we can teach kids about greenhouse design. But “thermal mass” (a material’s ability to store heat) and “glazing systems” are just terms that go in one ear and out the other for most students until they cross the greenhouse threshold. The experience is what makes those concepts meaningful.
When I led teens on backcountry trips in my 20s, my colleagues and I talked a lot about the four-stage experiential learning cycle we’d witness. A fight between paddling partners who end up tipping the boat? That’s the first stage: “concrete experience.” Stewing about it for a while? “Reflection.” Concluding that teamwork might be necessary for paddling is what’s called “conceptualization.” Trying that out and managing to canoe in a straight line is “experimentation.” Over the course of three weeks, they’d learn 50 lessons a PowerPoint presentation could never begin to teach.
Although the short greenhouse programs mean I’m never able to see all the stages, I can tell kids are having a powerful concrete experience that will kickstart the other steps. When they taste a bean, they begin to wonder what we’ll do with everything we grow. We tell them about Cochrane’s community fridge, where residents can bring extra food for those who need it. We talk about food security, and people who need to choose between buying a meal’s worth of protein or two meals’ worth of veggies.
I talked a lot with students about how a seed grows into something we can eat. It’s tempting— and sometimes necessary, because short attention spans—to end the lesson there. But a garden is so much more than what we see on the surface. Even beyond the root system that’s obvious when we pick a carrot, the plant actually feeds into a vast, delicate, and largely invisible network of mycorrhizae. These symbiotic systems of roots and thread-like fungus (mycelium) are essential to soil health, plant life, and ecosystem integrity. As biologist Merlin Sheldrake says in his book Entangled Life, “mycelium is ecological connective tissue, the living seam by which much of the world is stitched into relation.”
When most kids first heard that there are more microorganisms in a single tablespoon of soil than there are people on Earth, they thought I was making it up. I always gave a giggle when watching their eyes widen at the realization soil is actually alive.
It’s valuable, of course, to explain the finer aspects of growing and passive solar—kids love watching the pollination demonstration, touching building materials, learning about the importance of native plants, and exploring soil composition. But the first thing most of them comment on when they enter the building? Their senses.
“It smells like nature!” said one Grade 2 student, closing her eyes and smiling. My own kids quiet down and breathe more deeply inside the Roller, even if I’m making them do something “character building” like watering the plants. When we put our hands in the earth and support a living thing, we dig down to some very important truths about being human.
Creating these spaces for our young people is more important than ever. Natural disasters and extreme weather are already foisting a worrisome future at their feet. Even if they are not consciously aware, so many of the youth I’ve worked with feel it on some level—and are grateful for joy to supplant the worry.
When I work on community projects, I involve my kids as much as possible so they see the work it takes to make an idea into reality. One of Cultivate Cochrane’s goals is to build a massive community greenhouse where education, food security, and community-building can go hand in hand. But as a stepping stone, the board got a C$65,000 grant from the Canada Healthy Communities Initiative to build this way smaller greenhouse. The tiny Solar Roller allows my kids to take child-size bites of an idea that exists only as a sketch. Mini Ewe has favourite plants to visit, and Little Grey loves checking on his little box of worms.
Kids are always thrilled to hear that we think this might be the only passive solar greenhouse on wheels in North America. (Please be in touch if we’re wrong!) And they’re intrigued to learn that it’s an experiment we’re figuring out as we go. Will we be able to grow spinach in February? Follow along to find out!
Cultivate followed up our youth programs with visits to farmers markets and libraries over the summer. There’s a special kind of magic watching the kids I taught lead their parents into the greenhouse and tell them all the things they learned about helpful insects, native plants, and vermicomposting.
Even though their visits were often less than an hour, I heard from teachers that students would refer back to the experience through the rest of the semester. Some remembered shaking tomato flowers to “be the bee” and speed pollination along. Others recalled parts of a plant or a solar panel. My own son was able to articulate why the bean he planted earlier in the year wasn’t thriving based on what he saw in the greenhouse.
These tiny threads of experience are more powerful than they might seem. The best thing we can do as parents and educators is create authentic learning experiences for our kids; ones where they can see real-world connections up close. These opportunities branch out like fungal pathways, spreading roots and rhizomes through individuals and communities. My favourite feedback came from a student in my son’s Grade 1 class, who, after leaving the greenhouse, told their teacher, “When it was done, we wanted more!”
When I started this job, I saw myself as a guide through some basic biology and science curriculum. But as I watched students and my own kids explore the magical world of the greenhouse, I got the sense that something deeper—maybe even mycelial—was happening. Their experiences were feeding a whole new way of looking at the world around them.
Print Issue: Summer/Fall 2022