How to Compost at Home: 7 Things to Know
“Composting” is the word we use to describe the process by which soil microbes break down organic refuse into nutrient-rich humus, the fluffy black earth-stuff which sustains all terrestrial life as we know it.
The compost pile is a critical component of any well designed home and garden.
In an era of disposable culture and monolithic landfills as big as cities, compost serves as an excellent reminder of the second law of thermodynamics: that energy is never created or destroyed.
Permaculture aims to create closed-loop systems in which wastes from one element serve as fuel for the next – that’s how nature does it, and we’d do well to mimic her as closely as possible in this regard. Composting is one way to achieve this.
Now that I’m in the habit, it feels downright immoral to me to send all of the precious energy from our kitchen scraps and garden trimmings to a landfill, when I know that they could live many more lives by feeding next season’s vegetables.
This post is for those of you who are new to composting – maybe you’ve tried it before, maybe not, but perhaps you’re in need of some encouragement to go for it. I’ve distilled my years of composting successes (and disasters) into the following list of seven key points that will bring you up to speed and arm you with a working knowledge of how to compost at home. By the end of this article you should have a good sense of which methods and management techniques will work best for you in your specific situation.
1. Composting is really easy
The first and most important point I have to make is that anyone with access to a few square feet of outdoor space can compost. This shouldn’t come as a surprise, but making dirt is one of the simplest things you can do on planet Earth! Everything turns into compost sooner or later, so it’s pretty tough to get it irreversibly wrong.
You may worry about the aesthetics or the logistics of a pile of rotting food scraps: What will the neighbors think? What about stray dogs? etc. But I can assure you that whatever issues you may find in your initial assessments, there are techniques for composting that can help you work around them.
2. Compost piles can be hot or cold
Forget all of the terminology and jargon you might have picked up about various composting methods from other resources. That stuff is valuable, no doubt, but it’s really easy to get a lost down a rabbit hole of scientific comparisons and sterile (pun intended), over-complicated recommendations.
For the purposes of getting started, all you really need to know is that a compost pile can either be cold or hot, and there are good reasons for using both styles under different circumstances.
Cold compost is the simplest and easiest form: materials are added regularly, the pile is turned every few months, and the final product can take as long as a year to finish.
Hot compost is more labor-intensive and requires more logistical planning, but the final product can be ready in a matter of weeks. The pile is built all at once, and it must be at least one cubic yard in size in order to contain enough “fuel for the fire.” The ideal mix of ingredients (more on that later), combined with daily turning, leads to supercharged microbial activity that heats up the pile and significantly speeds up the process.
For the home-scale composter, cold composting is usually the way to go, because it doesn’t require you to stockpile huge quantities of materials or haul in external resources. If you do have access to large amounts of organic matter, and are in need of a great deal of compost in a short amount of time, building hot piles can be a good option.
3. Bins are great but not necessary
Before I started composting in our backyard, my biggest hurdle was settling on the most perfect design for a compost bin. How big should it be? Should it be covered? What about a three-bin system? And to say nothing of the materials I could use to build it...
These days our compost pile is, well, a pile on the ground. It’s not perfect, but it is the simplest and easiest thing to do, and it’s also the most natural.
If you’ve never composted before (or even if you have), just pick a spot, pile up your organic wastes in that spot, and watch what happens. This isn’t a life-or-death situation—I hope—so you can afford to just let nature do what it does and tweak your management style as you learn more about how your pile works in your unique situation.
If you need to keep animals out of the pile, be creative! There are as many design solutions as there are soil microbes in a pile of compost – that’s a lot! Go with a design that utilizes free or cheap materials if possible, and if you’re new at this, make it fairly easy to tear down. You’ll thank yourself in a few months or years when you come up with a better idea!
4. Everything turns into compost, but a few things should be avoided
As far as I’m concerned, if it’s organic matter, then it’s probably fair game for the compost pile. Some people will tell you to avoid things like meat scraps and animal products, but I really don’t think meat is a problem – just add it in moderation, and be sure to bury it well in the pile.
There are, however, some plant materials that should generally be avoided. Weeds and weed seeds are an obvious place to start, but volunteer tomatoes and potatoes are perennial weedy pests in many gardens due to their inclusion in compost piles, so you’re better off leaving them out as well. Some plants, like sunflowers, produce secondary compounds that inhibit the growth of other plants, so these should also be kept out of the pile.
5. Know the difference between “greens” and “browns”
When you make compost at home, what you’re essentially doing is adding small doses of potent nitrogen, in the form of kitchen scraps, to large piles of carbon-rich materials like yard wastes.
The nitrogen-rich elements are your “green” materials: these are organic wastes that are ephemeral in nature, breaking down very quickly due to their high concentrations of water and nutrients. Kitchen scraps, fresh grass clippings, and livestock manures all fall into this category.
Carbonaceous materials are your “browns”: sturdy, stable organic matter that can take many months or years to fully break down. This includes leaves, straw, twigs, aged grass clippings, sawdust, and woodchips.
The key to building a healthy and happy compost pile is to properly balance out these two components, so it’s important to know which category your materials fall into, and to have a plan to balance out any materials that you add.
6. Know the ideal ratio of materials, but don’t stress about it
There is exactly one rule of composting that you should be aware of:
The most perfect, balanced ratio of carbon to nitrogen in a compost pile is 30:1.
This is great to know, because a pile that is way out of balance can go one of two ways: either it doesn’t compost at all (too much carbon) or else anaerobic decomposition takes over and it becomes smelly and slimy (too much nitrogen).
The trouble with this bit of received wisdom is that comparing the carbon and nitrogen content of different materials can get extraordinarily convoluted. If sawdust has a C:N ratio of 400:1 and your cast-off lettuce scraps clock in at 15:1, how do you decide how much of each to add to the pile?
The answer is, don’t worry about it so much! Just make sure that your pile has a lot more browns than greens and you shouldn’t have anything to worry about. If you’re planning on composting scraps from your kitchen, though, keep in mind that this means you’ll need a healthy supply of carbon-rich materials on hand to balance out your pile. It’s helpful to keep materials like leaves and aged grass clippings piled up near your compost pile. When all else fails, you can always hunt down a straw bale or two.
7. Worms and chickens are great composting allies
When it comes to composting at home, you don’t have to go it alone. Both worms and chickens make excellent partners in the composting game, in their own unique ways.
Composting with worms—vermicomposting—is a fantastic alternative to traditional composting for household waste, and the end product is arguably even more valuable. All you need is a covered bin and a healthy starter population of worms (you’ll want to get these online, or else from a vermicomposting buddy – wild worms from your backyard won’t cut it) and you can begin harvesting beautiful, nutrient-dense worm castings in just a couple months.
If you keep chickens in your backyard, there are a few fun and interesting things you can do to put your flock to work recycling your organic wastes. The simplest method is to simply give most or all of your food scraps directly to your chickens. As omnivores, chickens can and do eat pretty much anything under the sun, and the list of foods to avoid sharing with them is quite short. And letting your chickens turn kitchen scraps into eggs is a more direct path to producing food for yourself than composting those same scraps anyway!
But if you have the space, plus access to several cubic yards of refuse, you can make a hot compost pile and let your chickens do almost all of the work. What you do is build up your pile inside of your chicken run/pen and then let your birds tear into it. If they are anything like our flock, they will go bananas climbing up and down the pile, digging and scratching for insects, microbes, and choice scraps, while at the same time adding their own, err, nutrients, and turning the pile for you.
After a day or two, they will have more or less flattened your pile, and you’ll need to go build it back up again. Let your flock work over the pile for four to six weeks, and before you know it they’ll be digging through some of the most beautiful, fluffy compost you’ve ever seen.