It wasn't so long ago that composting was considered a fringe activity, something you might find ardent back-to-the-landers doing out on their country acreage, but certainly not a practice within the realm of most suburbanites' experience. Today, however, many towns and small cities are encouraging composting like never before, sometimes offering compost bins at subsidized rates, often providing instructional materials or workshops on how to compost, while simultaneously ceasing the curbside pickup of readily compostable materials like leaves and grass clippings. At the same time, sales of bagged compost are way up, as are sales of all manner of composting equipment. Suddenly, it seems, composting has become mainstream.
Organic gardeners rave about it, but what's the big deal about compost? Why can't you just feed your plants some 10-10-10 and be done with it? Well, i's like the difference between eating a well-balanced meal made from fresh, natural ingredients, and eating a multivitamin and a bag of chips. In the short term, you'd be fine with either, but you wouldn't want to subsist on the latter diet for long. The same is true in your garden. Initially, your plants will respond vigorously to chemical fertilizers, but they won't attain the naturally robust good health they would if you provided them with compost. And with composting, you can be part of the cycle of life - instead of throwing away kitchen scraps and yard debris, you can turn them into valuable compost that your plants and soil will love.
Not only does compost contain all of the major plant nutrients (nitrogen, phosphorus, and potassium) in forms readily available to plants, but it also contains a wealth of minor and trace elements as well as billions (yes, literally billions) of bacteria, yeast, fungi, and other soil creatures that will continue to break down organic and inorganic matter in the compost and in your soil, providing a long-term, steady feeding of nutrients to plants.
In addition, because of its loose, fluffy, cake-flourlike texture, compost improves the tilth, or structure, of all garden soils, both increasing the drainage of clay soils and binding together sandy soils, enhancing their moisture retention. Regardless of where you garden or what you grow, compost will make your plants healthier and more vigorous and increase their flowering and fruiting like no other substance you can give them. Simply put, composting is the best possible thing you can do for your garden.
How Long Does It Take?
Many gardeners don't compost simply because they perceive it to be more difficult or complicated than it really is. In truth, composting---rotting really---is a natural process that will occur even without any effort on a gardener's part. If you just put all your garden waste, kitchen scraps, grass clippings, and autumn leaves into a giant pile, you'd have good, usable compost deep within the pile in a year and a half or so.
Actively engaging in the composting process just speeds the whole process up greatly. Researchers have found that it's possible to make finished compost (that is, compost that is so completely broken down that none of its component materials are distinguishable) in as little as 10 days. Practically speaking, most home gardeners can make a good batch of compost every 3-4 weeks; over a growing season, that's a lot of free fertilizer of unparalleled quality.
The ABCs of Composting
So, how do you make compost? There are four key words to remember: green, brown, air and water. What this means is that, to make compost, all you have to do is bring together moist, fresh, predominantly green ingredients (grass clippings, weeds, kitchen scraps, and the like) and predominantly brown ingredients (dead leaves, straw, hay, wood shavings or chips, etc.), ensure that the mix remains damp, and turn it all every few days to reintroduce oxygen to the pile.
Adding worms to your on-ground composter and or garden soil will also speed up the composting process, and will add extra soil nutrients (from the worm castings). Keep adding worms from your finished compost back into fresh material. That's it. In less than a month, you'll have rich, crumbly, brown compost that you can add to your garden soil, use in containers, or mulch with.
Containers and Ingredients
Compost can be made anywhere, in virtually any kind of container, or in no container at all---just a big pile. A bin or tumbler will keep the process neat and manageable, however, and will make it easier to add air to the mixture. To start your compost pile, reduce the size of the ingredients you're using in the pile by chopping them with a machete, a sharp garden spade or other tool. Autumn leaves can be shredded quite well by repeatedly mowing over them. Then add all the ingredients together, layering them in 3-4-inch-thick layers if you're using a bin, or just tossing them together if you're using a tumbler of some sort. Strive for somewhere between a 5:1 and an 8:1 ratio, by volume, of brown materials (fuel for the organisms that will decompose the pile) to green, but don't get too fussy about it---if the proportion is off, it's easy enough to recognize and to remedy.
There are many different styles of outdoor compost bins that fall into one of two categories:
A rotary-style composter can be placed anywhere and keeps all the material organized and off the ground—important features for some yards. Rotary composters produce compost quickly because they are easy to turn and aerate the material, but they tend to dry out more quickly.
An on-ground compost bin keeps material contained and in contact with the soil, which helps keep moisture content high and adds naturally occurring microbes and worms to the process. Consider using two bins at once: one to pull finished compost from and another to add new material to. Switch the bins once your finished compost is depleted.
It's optimal to have a small cart at hand around the yard and garden to collect and organize compostable materials from weeding, pruning, clipping and raking.
Kitchen countertop compost crocks offer a clean and efficient way to collect kitchen scraps. While a one-gallon size is good for small families, a one-and-a-half-gallon container works for larger needs. Options range from plastic to ceramic to stainless steel. Each compost crock comes with charcoal filters to eliminate any smells in the house. You can also place biodegradable liner bags directly into the compost.
Green and Brown: Getting the Balance Right
A pile that doesn't heat up within 24 hours needs more green material. A compost thermometer is very handy for determining the temperature near the center of the pile, which should rise to approximately 150-160F. Often, however, you can see a pile steaming and can feel its heat even from the outside of the tumbler or over the top of the bin. A pile that develops an ammonia-like smell needs more brown materials; just work some more into the pile, and the aroma should go away.
Moisture and Air Speed Decomposition
The air and water requirements of a composting operation are similarly low-key. The mixture of materials should remain about as moist as a wrung-out sponge---damp, that is, but not soaking wet. If the mixture seems too wet, damp is perfect, give it a turn to mix and aerate. Layer in some dryer material, stems or straw to help the air flow. If it is too dry, sprinkle on some water and add fresh, green leafy material. Remember, the more often you turn a pile, the quicker you'll have compost, because most of the composting process is carried out by aerobic (oxygen-using) bacteria. If you decide to build your pile in a traditional square bin, you'll want to have an extra bin next to it, so that you can move the pile from one bin into another. If you use a tumbler of some type or rotary composter, turning is easier yet: All you have to do is spin or roll the container to re-oxygenate the pile.
Tips and Troubleshooting
Not much can go wrong with a compost pile other than the two conditions mentioned above---a pile that doesn't heat up and one that develops an ammonia-like smell. Altering the ratio of ingredients one way or the other will generally correct things. You can prevent any problems with critters visiting your pile by keeping animal and dairy products out of your kitchen compost container. Vegetable and fruit scraps are excellent "green" additions. When your compost looks black and earthy and most of the added material has become unidentifiable, it is ready to use.
Using Your Compost
Once you've cooked your first batch of compost, what do you do with it? As mentioned above, it's excellent as an addition to garden soil, container mixes, or used as mulch. Depending on the ingredients you used, there may be coarse pieces still in the compost. If you intend to use your compost as mulch just leave it coarse, however, if you plan on using it as potting soil or for seedlings, you'll want to break down these coarse pieces. The best way to deal with these is to screen the finished compost through a piece of hardware cloth stapled to a frame (or through a "riddle," a tool designed for just such a purpose).
Starting All Over Again
Anything that doesn't sift through the screen can be returned to your pile or bin for further breakdown. And be sure to save a bit of finished compost to start the next batch: The rich microbial life within that compost will get things off to an even faster start next time around.Back to Top