Composting is the ultimate in recycling. In what other endeavor can we take things meant for the trash -- those banana peels, apple cores, fall leaves, weeds, and animal bedding -- and turn it into something that will literally transform our garden. Pretty amazing stuff! While there are some rules to follow when learning how to compost, rest assured that they're pretty basic, and that, in the end, no matter how many "mistakes" you make, compost just happens.
Bin, Pile, or Tumbler?
The first consideration in learning how to compost is figuring out what you're going to compost in. A lot of this will depend on your garden and what you think will work best aesthetically and size-wise. A large garden will probably require at least one large pile, while a smaller garden can get away with a small tumbler or other small-space composting solution. If you're interested in buying a composter, here are a few things to consider:
- How much will you be composting?: If you have a large garden and yard that produces plenty of organic matter in the way of grass clippings, leaves, small branches, etc., then you'll need a bigger system to handle all of those inputs. If, however, your yard mostly produces the occasional spent flower or weed, and you have very little lawn (or use a composting mower) then a more compact bin or tumbler will do.
- Aesthetics: You may not want to have to look at your compost pile all the time. Can you build your compost bin behind a garage or other building? And if you can't, and the sight of an uncontained compost pile bothers you, you will probably want to look into a pre-made bin or a way to decoratively fence off your compost area.
- What are you capable of turning?: While compost happens, and you can simply pile organic matter and let it decompose, it will happen faster with occasional turning. If manually turning compost is difficult for you, consider a tumbler, pre-made tumbling-type bin, or a worm bin.
No matter what you choose, your bin or pile should be placed in an area that is easy for you to access, preferably in at least partial-sun (the warmer it is, the faster the contents will break down).
What to Compost
In general, plant matter can be composted. If it, at some point, was a plant, consider it good for the compost bin. This automatically eliminates meat, bones, and dairy, which should never be added to a compost pile because they may harbor harmful bacteria and attract pests.
We categorize potential compost ingredients into two groups: "greens" and "browns." "Greens" are nitrogen-rich, tend to contain more moisture, and break down faster. "Browns" are carbon-rich, contain less moisture, and take longer to break down.
"Greens" include vegetable scraps, grass clippings, weeds, coffee grounds, animal manure, and egg shells.
"Browns" include fall leaves, straw, shredded newspaper, cardboard toilet paper tubes, twigs and small branches, and sawdust.
Related Content: 50 Things You Can Compost
These items can be added to your compost pile in carefully-planned layers (which is how you often see it described in books and magazine articles) -- but who has piles of leaves and grass clippings and vegetable scraps just sitting around, ready to layer into a compost pile? The easier way is to just add them to your pile as you accumulate them, and turn the pile occasionally to aerate the pile and mix the "greens" and "browns" together.
What About the Ratio of "Greens" to "Browns"?
Oh, yes. Those ratios. If you are obsessed with the idea of having finished compost in the shortest possible amount of time, then you need to pay strict attention to the ratio of "greens" to "browns" in your compost. That ratio should be 30 parts "browns" to one part "greens."
The average garden produces more "greens" than "browns" in general. If you're not obsessed with fast compost, just go ahead and add items as they come up. If you find your pile getting soggy or not breaking down much, add more carbon-rich items like fall leaves or shredded newspaper. In general, it's not something most gardeners need to stress over. Compost happens!
How to Maintain a Compost Pile or Bin
The main considerations in maintaining a compost pile are turning it regularly and maintaining the optimal moisture for decomposition.
Turning the pile can be as large or small an undertaking as you need it to be. If you have a tumbler, simply give it a spin every day. If you have a bin or pile, there are a few ways to manage it. You can get in there every week or so and use a shovel or garden fork to turn the entire pile. This adds great aeration and really combines the contents. If you have a strong back and want compost a bit faster, go for this method. However, if you're less than thrilled at the idea of shoveling all of that organic matter, you can simply jab a garden fork as deeply into the pile as you're able, and give it a back-and-forth wiggle. This will add air to the pile, which will hasten decomposition. You won't get compost as quickly, but if you're interested in making compost and saving your back, it works well enough.
The other maintenance issue is maintaining adequate moisture. The contents of your compost pile should be as moist as a wrung-out sponge: evenly moist, but you shouldn't be able to squeeze any excess moisture out of it. If it's too wet, it will smell. If it's too dry, decomposition will slow to a crawl.
If you find that your pile or bin is too wet, turn it, adding plenty of shredded newspaper or fall leaves as you do. These "browns" will soak up some of the excess moisture. Refrain from adding greens for a while, until the pile returns to a normal moisture level. If rain has been an issue, cover the pile with a tarp during rainy weather.
If you find that it's too dry, simply give it a spray with the hose or watering can. Likewise, you can make a bit of a "well" in the top of your pile and add water to that -- the water will seep down into the pile and moisten the contents at the center.
Using Your Compost
Once you have finished compost (which looks and smells like dark, rich soil) you can use it in garden beds, on your lawn, in container plantings, and even as an ingredient in your seed-starting mix. It's nearly impossible to add to much compost to your garden, so feel free to go compost-crazy!