Easy Ways to Compost (& Vermicompost) in Small Spaces
Updated: Dec 8, 2020
Read more from Brianna on how to reduce your food waste at home.
As we enter another month of gorgeous summer weather, many are turning to their small gardens to watch plants blossom and grow. But for many with small growing spaces, it can be difficult to sustain plant growth over the long term without continually buying expensive soils and fertilizers in disposable containers. To avoid this wasteful process and still provide nutrients to my plants, I started investigating how to compost in a low waste and space-efficient way. What I found was that by following the basic rules of composting, I could create a low waste compost system both on my balcony and inside my apartment without it costing me tons of money, time or resources. Let me show you how!
There are many sites which cover the basics of composting in detail (see for example: How to Compost, the Composting Process or Compost Bin Ideas), but what you need to know is this: composting is the process of breaking down (decomposing) organic “waste” such as food scraps, leaves and branches so that the nutrients in those materials can be absorbed by other plants. By mixing compost into the soil in your garden/planters, you are providing essential nutrients for your plants to grow (see: Plant Nutrients) while also helping retain moisture in your soil.
So how do you actually create compost?
Well, to create the conditions for decomposition to occur, you need 1-part green material (such as kitchen scraps) and 3-parts brown material (like cardboard, fallen tree leaves, or straw), plus water and oxygen. In larger gardens, this mixture is usually accomplished in large composting bins which (due to the amount of material in them and the heat generated from them) can breakdown materials quicker than the smaller compost bins that we’re focusing on today. (See quick tips at the end!)
So how do we make this process efficient on a smaller scale while still maximizing our available space and keeping the project low waste?
We have two main options: a) “cold” composting in bins or as part of a planter outside, or b) using worms in a vermicomposter inside.
Cold composting on a balcony
Balcony composters can be stand-alone units (like this Bin or Stacked Composter) or if space is at a premium, they can be part of a planter (original design here). These are "cold" composting options because they take longer to break down materials, but both are viable options if you have a small outdoor space and a container. The downside of the planter composter is that all the designs I found were made out of plastic containers (with air and water holes drilled in) which raises questions about how the waste "bits" are disposed of. So I decided to see if I could make a composter planter using materials I had on hand.
After lining a milk crate with a used burlap bag (picture #1), I created a smaller container (the "composter") within the "planter" using a sheet of cardboard. I then added soil around the outside of the composter to insulate it, help retain moisture and act as another space to grow plants. Inside my mini composter, I thoroughly mixed together 75% browns to 25% greens (all of which came from my apartment building) and added water to start the decomposition process (picture #2). Shortly after that, I planted some seeds around the composter, added some more food scraps and covered the top with a thin layer of soil to keep the pieces from flying away in the wind.
One month into this experiment (picture #3), I am fairly pleased with my project:
Pros: all materials were repurposed so the project was low waste and zero cost. The materials I put in originally have started to break down, my seedlings have popped up and it doesn’t smell! My failed sourdough starter also helped introduce some beneficial bacteria to the mix
Cons: the milk crate and burlap side cause the planter to drain too easily. I'm having trouble retaining water on hot days which slows down the decomposition process and stresses the plants around the perimeter of the composter. This system also only fits 2 small green bins worth of scraps, so we can't compost all of our kitchen waste on-site.
My next step is to create a second balcony composter out of an old plastic planter box I salvaged from one of my neighbours. It takes up more space, but its size will help retain more water and hold more compost. I can also put one of my planters on top to save space if need be. This alternative will work better for my situation, and it's still low waste because I'm using salvaged materials I already had and I'm not creating more waste. On top of that, I'm not changing the function of the planter- it can still be used as a planter in the future by me or someone else.
Vermicomposting in an apartment
In vermicomposting, worms eat the organic waste and their droppings (called “worm castings”) are used to fertilize the soil. Since worms like cool and dark places, worm bins are often placed inside one’s house (e.g. under a side table in the kitchen, or under the sink). A worm bin can be made out of a single plastic storage container and lid (with air holes drilled in: see Creating a Simple Worm Bin), or it can be more elaborate (see: Building a 3 story worm house). As long as the worms are fed the right mix of food regularly (and their bedding stays moist) vermicomposting can be done year-round and odour-free so they are a great low cost and a low waste option for composting most of your food waste at home.
Come the fall, I hope to switch to vermicomposting to handle most of our kitchen waste as this seems to be the most efficient use of space. However, part of that transition is making sure everyone in my family is comfortable with having worms in the house, and sourcing second-hand materials (e.g. plastic storage container and newspaper) to suitably house the worms. Like many low waste lifestyle changes, successful long term change takes some careful planning. There needs to be some level of understanding and comfort with the idea among family members for larger changes like this to be successful. Adaptation and perseverance are key!
While you may never have enough space for all the plants you want, you may already have the space to create a composter on your balcony or a worm bin in your home. The planter composter I created was a fairly straightforward and easy project, and I'm really looking forward to having compost (and hopefully worm castings) for my garden in the near future! I hope that this blog has given you some new ideas for your space and that you will join me in this low waste composting journey!
Quick tips for success:
If your compost or worm bin smells bad (i.e. rotten, funky, methane-y), its not working properly. Make sure you have the right mixture (browns, greens, water, oxygen) in your compost bin and try again. For your worm bin, make sure you are only adding as much food as your worms can consume in between feedings, and don't let the bedding get too wet.
Don't put meat or dairy products in your compost or worm bin because these materials need higher temperatures to effectively decompose (see 'What not to compost')
Avoid adding onions and citrus to your worm bin- worms don't like them.
Cut up your green and browns so they break down faster in a composter. Make sure to mix everything together to introduce air (oxygen) into the mix!
Celebrate your successes! Even the little ones like getting finished compost or worm castings from your project
Brianna is a community planner who is passionate about sustainability and living a low waste lifestyle. Since 2017, Brianna has been striving to live a "zero" waste lifestyle while being a full-time student and now a working professional. From making her own personal care products to rejecting disposables and finding creative new uses for items past their prime, Brianna has been actively searching for sustainable ways to reduce her waste long term. She is excited to learn from and share her diverse knowledge with the Network to help others continue their low waste journey.