Reducing the Impact of Food Waste with Composting
Updated: Aug 2, 2019
Just as 'recycle' is last on the 'reduce, reuse, recycle' waste hierarchy, composting is at the bottom of the food recovery hierarchy. The top levels of the hierarchy are the best ways to prevent and divert wasted food because they create the most benefits for the environment, society, and the economy.
While less preferred than reducing the amount of waste generated in the first place or recovering discarded food to feed humans, composting does reduce the amount of food waste going to landfill - food waste is the largest component of landfill volume and causes the release of methane gas, a far more potent greenhouse gas than CO2. Furthermore, compost acts as a natural fertilizer for better yields in your garden and can both loosen dense clay soils and help sandy soils retain water. Today in our continuing blog series on food waste, we're going to work our way up from the bottom of the food recovery hierarchy and talk about ways to make composting more approachable and accessible.
For People Who Don't Have Much Space
You don't need a large space to compost. You don't even need an outdoor garden. In fact, you can begin composting on your kitchen countertop or freezer! Use a kitchen compost collector with a carbon filter and/or a design that allows oxygen to move through your kitchen scraps (the growth of anaerobic bacteria in an airtight compost bin is the culprit behind the most offensive compost bin smells) . You can even collect compost in your freezer! If you're especially concerned about odors or annoying flies, you can set a small bin designed to go on your freezer door and add scraps there. This is virtually odor-free as the scraps will freeze!
What can I do with compost if I don't have an outdoor compost pile or bin?
Most American cities don't yet have curbside composting for food waste. The best way to compost indoors in an apartment or other small space is with a vermicomposting bin. Yes, that's right - worms! No, the worms don't 'go all over your house', they don't stink, and it's actually a very clean method to turn those food scraps into 'black gold' without a backyard bin or pile. Composting worms are not the earthworms you see outside; they're usually red wigglers and they're especially suited for the job.
Commercial worm bins are specially designed to make collecting finished compost easy (there are lots of blog posts out there about DIY vermicompost bins with things like old 5 gallon buckets, but they're generally ugly. Fine (and frugal!) for indoors if you don't mind ugly, but less convenient and attractive than a commercially purchased worm bin. Click here for a great website where you can purchase bins that also has lots of resources and education about vermicomposting.
If the idea of a vermicompost bin indoors freaks you out (but it really shouldn't!) you can ask around at your local farmer's market - there may be a farm willing to take your food scraps off your hands. Locally here in Detroit, Midtown Composting picks up compost weekly from both residents and businesses - see if your community has a similar pick up service available.
If you're using a bag in your kitchen compost collector, keep in mind that the vast majority of bags for kitchen compost bins are designed to break down in industrial composting facilities, not in backyard compost piles. If you're adding your kitchen compost bin into a larger pile, dump the bag of scraps and then discard the bag, as it will not break down.
What About Rats and other rodents?
If you know your community has a rat problem, the idea of a loose outdoor compost pile might be scary. In my yard, I have a chew-proof plastic 80 gallon tumbler with holes large enough to let air in but small enough to keep rodents out that allows me to turn my compost as necessary. I have not had a problem with rats, rodents, or bugs.
What about smells? I don't want rotting food smells in my house!
Generally, if your carbon-rich brown (paper/cardboard/leaves, etc.) to nitrogen-rich green (grass clippings and food scraps) ratio is about right, your compost pile will be virtually odor-free and you'll have relatively speedy compost. The problem is that in your kitchen compost bin, you're not really collecting 'browns' - it's all greens. There are hard-core 'crunchies' that would balk at this, but I find that bad smells in an indoor kitchen compost bin are almost always a result of the same types of food, and I avoid putting those foods in my kitchen bin.
Those foods are are:
Potatoes (skins are okay, but no white parts)
Broccoli
Cabbage
Onions (skin is okay)
Lemon and orange peel - the smell of rotting citrus makes me gag!
Dairy and meat
Spoiled food (overripe fruit is fine, but not green fuzzy things in the back of the fridge)
It goes without saying that unless your community has a curbside collection program and allows for them, never put dairy products or meat in your kitchen compost bin - the risk of stink is just too high. I also avoid adding kitchen oils, even if they're vegetable-based- it slows down the composting process too much.
But I make sure my family wastes very little food. Why would composting be useful for us?
Even if you have done such a great job of reducing food waste that you NEVER waste a single ounce of edible food (and let's face it, virtually NONE of us are in that category), you're still going to have bits and pieces of fruit and vegetable scraps you can compost - apple cores, banana peels, carrot peels, etc.
I have finished compost but I don't have a garden. What do I do with it?
Give it away! Gardening friends or vendors at your local farmer's market would love to take it off your hands. You can also add it to your houseplants!
Stay tuned - the next installment of our Food Waste series is on the middle part of the Food Waste Hierarchy - industrial and agricultural uses for food scraps and recapturing discarded food for feeding people.