A Compost System for Apartment Living
By: Talia Knowles-Rivas
Tags: Gardening, Plants, Food Waste, Food, Garden

A Compost System for Apartment Living

A city-dweller’s guide to dealing with food waste.

For inner city folks, I’d say we cook a lot: at least five nights a week and mostly vegetarian. It keeps the costs down and our guts healthy. Cooking mostly vegetables reduces the amount of packaging we bring home and eventually discard – which was great – but we quickly became aware of how many veggie peels and skins we were tossing into landfill. We keep a modest organic vegetable garden spread across pots and planters on our patio and it seemed a waste to toss out all that vegetable matter instead of returning it to the soil.

Living as we do, in a small urban space, we thought that composting wasn’t something we could accomplish. It seemed like an activity that would require loads of space and potentially stink up our patio. We tried getting creative with our food waste and explored communities like ShareWaste to gift our organic matter to local composters who were hungry for more material. Finally, after much research, we discovered that if we paired two compost processes together (one in the kitchen, one in the garden) we could get a nice little system going.

But First, Bokashi!

The bokashi system uses anaerobic digestion to breakdown food waste into a smaller waste amalgam. Most bokashi systems on the market look like small waste paper bins and can be stored in a kitchen or laundry. It takes about 2 weeks for a full bokashi load to decompose to a state that’s ready to join the garden compost bin. We feed our food waste into the Bokashi first and when it’s full, we empty it into a large, DIY compost bin that we keep on a small strip of garden on the patio. This system really works for us because it stops the outdoor compost bin filling up too quickly (and we only have space for one out there).

Making a DIY Outdoor Compost Bin

Head to your local hardware store and pick up a big plastic garbage bin. If you’re Australian, like us, a trip to Bunnings and $30 AUD will get you a 75 litre bin. To create our compost bin, we took a knife and created 50mm holes, 200mm apart in a single line: from the tip of the lid, to the base of the bin. We repeated this four times to create four, even quadrants. The holes are to encourage aeration. An outdoor compost bin uses aerobic digestion to break down the material, so aeration is very important. In addition to the bokashi, we regularly deposit equal layers of brown matter (carbon-rich materials) and green matter (nitrogen rich materials) and turn it regularly so that the worms are sure to access all matter, equally. Keep your bin in a warm spot in the garden so it’s easy to access. If you don’t have a small strip of earth to plonk your bin on, see if you can start one on the roof or in the courtyard of your apartment block (near where the landlord keeps your standard garbage bins).

Our DIY Outdoor Compost Bin

Coverting Compost to Soil

It took three months to turn our first outdoor bin full of food waste and brown matter into rich compost, ready for the veggie garden. To check if your compost is ready, assess the state of it by turning, thoroughly. If you think it’s looking good, lay out a tarp and carefully empty the bin onto it. Leave the emptied compost sitting on the tarp for fifteen minutes to allow the worms time to crawl away from the light, and down deeper towards the bottom of the pile.

Scoop your soil from the top of your pile, being sure to separate out any matter that hasn’t yet fully transformed and return it to the compost bin with a thin layer of soil to start your next batch. Voila! Now you have fresh compost for your little urban garden.

Good soil is hard to find

It can be difficult to improve your soil if you’re gardening in a city setting. Whatever form your garden takes — pots, planters, kerb-side strips or a small patch in the backyard — generating compost gives you a regular source of nutrient-rich top soil to give it a much needed boost. We try to align planting with when a fresh batch of compost is likely to be ready. It gives our veggies the best chance of thriving.

Between generating compost and sourcing regular batches of worm wee from some co-op friends, we’ve managed to grow potatoes, carrots, tomatoes, butter lettuce, broccoli and a range of herbs in the last twelve months — all of them in pots. So if you’re living in an apartment and keen to reduce waste while generating top quality soil for your potted plants, get a composting system started!

Read my latest post on ten tips for starting an urban edible garden.