As far as I can tell, compost is basically magic. I throw moldy bread, banana peels, and some broccoli trimmings into a bin, and with very little work and some time… poof! It transforms into dark, rich, healthy soil that helps house plants bloom, gardens grow, and all plants live happier, healthier lives.
Learning to compost takes only a few minutes and can help you save big: no more need to buy expensive chemical fertilizers or “plant food”. Turning your coffee grounds, banana peels, and vegetable trimmings into a useful product will also seriously cut down on the trash you throw out.
But isn’t compost stinky?
No! When food rots it gets stinky. But properly set up compost systems don’t let the food rot. Instead, air-flow and break-down keeps it transforming into soil instead. Read on for easy step-by-step instructions to set up your very own indoor, apartment-friendly compost system – without the smell.
Compost has 5 key ingredients: “greens”, “browns”, soil, water, and air. We’ll tackle them one at a time.
This really means nitrogen-rich material, and it covers almost all your daily kitchen scraps. Vegetable trimmings, apple cores, banana peels, even eggshells and stale/moldy bread. Each item has different nutrients, so healthier soil comes from a diverse compost pile!
Browns include things like coffee grounds or tea leaves (untreated paper filters are usually ok too! just watch out for tags, strings or staples on tea bags). They also can include dry lawn “waste” like leaves or dry grass clippings. I like to keep a container of leaves handy near my compost bin to pile them in as needed. No lawn? Shredded up newspaper works too!
There’s two good reasons to use soil in your compost bin: a scoop from outside has a few itty bitty soil critters living in it. These critters are great at quickly breaking down your food scraps into dirt! A thin layer of soil also acts as a smell blanket – keeping any stink inside.
Compost “cooks”, or breaks down into soil, best when it is the texture of a wrung-out sponge. Usually your kitchen waste is wet enough to keep it cooking fine. You can test this by poking a stick into the pile and seeing if it’s damp when you pull it out. If not, sprinkle on a bit of water.
Air flow helps break down the kitchen scraps, and helps keep the process “aerobic”, which is good. “Anaerobic” – without oxygen – gets much stinkier. Air flow comes from holes in your container, and frequent “turning”. I usually mix my compost with a hand spade about once a month.
For apartment-sized compost, aim for a 10-20 gallon container of your choice. A metal trashcan works, or a plastic box with a lid. If you chose wood, be sure it’s treated so the wood doesn’t join in the decomposition inside!
If you have a really small space, you can use a smaller container, like a plastic trash bin that fits under your sink. Just be sure it has a cover!
To let the air through the compost, drill/puncture at least 10-12 holes through the bottom and set the container on slats to let air flow underneath. I like to put some newspaper underneath the slats to collect any possible spills – usually just dirt!
You’ll need two similar containers – when the first is full, it can “cook” while you start filling the other. Your first batch of compost should be ready before your second container is full!
You know the ingredients; you have your container. Now let’s put them together!
- Start the bottom of your container with a thin layer of browns (I like to use a few twigs and leaves, or shredded newspaper).
- Then add a layer of greens. You can add them bit-by-bit from your kitchen as you make waste. When you have about an inch thick across the layer, move on.*
- Pour a thin layer (¼-½ inch deep) of soil across the compost. This locks down smells and starts the decomposition.
- Continue adding these lasagna-like layers (browns, greens, soil) until your container is full!
- When your container is full, cover it. Be sure to keep the cooking compost moist and aerated by checking the moisture levels and turning (mixing) it at least every few weeks. By the time your next container is full, you should have no more kitchen waste and just smooth dark brown soil to feed to your hungry potted plants or garden!
- *If you start smelling a stink, try covering your greens layer with a thin layer of soil.
- Always avoid meat and dairy. These don’t break down in small household compost piles. They just rot, stink, and attract vermin. So stick to fruits, veggies, coffee, and eggshells for now.
- Smaller is better. If your whole head of lettuce goes bad, chopping the lettuce into 1” or smaller chunks before dumping it in the bin will help it decompose faster and stink less.
- You can do all of this outside, too, if you have a yard. Experts recommend a 3’x3’x3′ “bin” space in the yard. For creating your greens layer, I’d keep a small collection container inside. When your indoor bin is full of kitchen waste, carry it out, dump it on, and immediately add your soil layer to keep down smells and flies. The air and water needs are the same – turn the pile with a big spade or fork every few weeks until it looks like dirt!