By Russell Vinegar
I’ve been thrilled to have to the opportunity to enrich our gardens and greenhouse as productive and educational community spaces, and bring more food production right to our site. As a camp and outdoor centre with fostering stewards as its mission, it is only natural that we should lead by example and in most areas I’m impressed by our efforts – phenomenal outdoor and environmental programming led by motivated and knowledgeable staff, sustainable architecture, and local food sourcing. But when it comes to growing food, there’s one issue: we haven’t got much soil. The answer: start making our own. How? Upcycle our food ‘waste’ into compost!
While our distinctive alvar landscape – shallow soil (rarely as much as a 10”) over limestone bedrock nearly 500 million years old – is charming and supports rare and unique prairie-like ecosystems, it creates some challenges for vegetable production. Fortunately, by addressing our need to create more soil, we can also tackle our food ‘waste’ issue/opportunity.
Nature teaches us there is no waste: if a tree falls in the forest, microbial decomposition will, in time, return it to soil, where it will support new life. It isn’t hard to extend this concept to how we might better manage waste on our site by ‘closing the loop’ of nutrient cycles. That’s why I put ‘waste’ in quotations. Even though this food might be past eating, it offers us an incredible opportunity to build soil.
Believe it or not, we produce over 11 tons (22 000 lbs) of food waste each year at Camp Kawartha. Currently, most of that waste ends up in landfills, where it releases greenhouse gases and contaminates soil and groundwater. We spend roughly $6000 each year on garbage disposal, and could save over $2000 by taking food out of the picture.
We are lucky to have local farmers to pick up our waste in the summer for their pigs, the day is not far off when they will retire from farming. Plus, we have been buying soil and compost each year to build our gardens, when we could be producing it ourselves.
Conventional composting was tried before at Camp Kawartha, but bears were reportedly attracted, something probably contributed to by the amount of cooked food waste incorporated or improper management. Besides requiring intensive management, like turning and managing carbon:nitrogen ratio, not all foods can be composted.
Luckily, our food services manger Dawn McKenzie introduced the concept of bokashi fermentation – a type of composting system that uses specialized microorganisms to rapidly convert food waste into compost. Besides not producing any odors, bokashi also has the advantages of accepting all types of food, including meat and cooked food; rapid decomposition (less than 1 month in summer); low cost relative to in-vessel composters, like the one at Lakefield College School; simple management requirements (no turning!); and enriching soil with microbes, making more plant nutrients available.
To make a long story short, bokashi is a two-step process in which food is first fermented (think pickled) by special microbes in a sealed barrel, and then mixed into soil where it is decomposed by soil microbes. For more information on how the process works and what our plans for bokashi at the camp, we will soon have a webpage online where you can learn all about it.
Never heard of bokashi? I hadn’t either. While I’ve been hard at work figuring out the details of how we might create a large-scale system to handle all of our food waste, I’ve also started some smaller trials. And, even a bit to my surprise, it seems to be working! As anyone who has eaten a pickle knows, a pickle doesn’t look all that from a cucumber, but all sorts of delicious changes have happened inside. Well, the fermented food waste looked pretty well the same too when I mixed it with soil in a planter in the greenhouse. Only two days later, I could feel the heat coming off soil – a sign that aerobic soil microbes were munching away. After a week, things had started cooling down and what was left of the food waste was limited to soft crumbly chunks from big stuff like apples. I plan to fill the bed with a variety of herbs for the kitchen to enjoy throughout the year, so I decided to pop in some nasturtiums and see how they fared. A week later, they look great!
We’ve got a larger scale trial going now with big barrels. At the end of the April, these guys will be fermented and we can start adding the compost to our garden beds, just in time for spring planting. If all goes well, we will keep the bokashi composting going year round and be producing 20 cubic yards of compost every year – enough to fill 35 10’x3’ planters with 2’ of soil each. Forget about buying topsoil – here’s to ‘waste’!
