The Basics of Composting
Compost Happens—sounds like a bumper sticker, but it’s true. Collect a bunch of plant debris into a pile and as long as it doesn’t dry out, you’ll get compost … eventually. With a little help, you can speed up the process. There are several ways to compost; one to fit every conceivable personality, from the type “A” to the couch potato. Try one method to start with and as you gain experience, adapt it to your particular lifestyle. Above all, keep your system simple and convenient. The two most popular ways to compost we’ll call the passive method and the active method. Since the summer gardening season is right around the corner, we’ll focus on the active method because you get results much faster. First things first, you will need a place to keep your compost. If you have the time and energy you can find books at the library or information online on how to build your own bin. If not, you can purchase your bin pre-constructed.
Active Compost Method
Building a pile the active method way is not a gradual affair; the ingredients must be added all at once. The bulk is a key factor determining whether the pile can retain heat well enough for the thermophillic bacteria to kick in. When things start to cool down, the pile is physically turned which aerates the pile and it heats up again. This process is repeated a couple of times until the pile becomes compost. Because of the high temperatures, pretty much any plant material can be thrown into the pile. However, it’s still probably wise to avoid adding obviously diseased plants. The beauty of the active method is that you can have beautiful brown compost in just a couple of weeks.
Hunt and Gather
Collect enough “browns” and “greens” to build a 3x3x3 foot or larger pile. Active composting is a “hot” method and bulk is necessary in order for your pile to retain heat. The pile should contain about 50% high-carbon material and 50% high-nitrogen material. This ratio can be adjusted up or down depending on the quantity and quality of the materials at hand.
Shred and soak
Try to chop up any large materials. A shredder is not neccessary, but reducing the particle size can help speed up the process. Leaves can be run over with a lawn mower or dry leaves can be placed in a plastic bag or trash can and stomped on to break them up. It’s helpful to soak your browns in water overnight before you build the pile. This step is particularly helpful in the dry southern California climate. Composting time can be cut in half if you soak your “browns”.
Layer, mix, water, and cover
To build the pile, start with about a four inch layer of “browns” then a four inch layer of “greens”. Mix the two layers together then water thoroughly. Continue layering, mixing & watering until your bin is full. The layering is suggested only to make it easy to judge how much “browns” and “greens” have been added. Layering is not necessary but makes it easier to measure and mix the “browns” and “greens” more uniformly, which your compost microorganisms will appreciate. A cover on the pile will help it retain heat and water during the dry season and shield it from a drenching during the wet season. If the bin isn’t equipted with a cover, flattened cardboard boxes work well (and it’s a good way to recycle the cardboard). Just lay the cardboard on top of the pile and water it down.
Turn, turn, turn
Temperature is the most accurate way to tell when to turn the pile. Normally, within 24 to 48 hours, a new pile will reach temperatures of about 140 F and will sustain this temperature for several days. When the temperature drops below 120 F, turn the pile using a pitchfork, breaking up any clumps and moving the outside parts to the inside of the pile (the insides compost faster than the outsides). If the pile is too dry, this is a good time to water it again. Cover the pile again and wait. The temperature should peak again in about a week or so. As soon as it begins to cool, turn the pile once more. In a week or two, your compost should be finished.
When is compost “finished”?
The easiest and best way to tell if your compost is finished is to take a look at it. The compost should be dark and crumbly, fresh-smelling, with very little of the original material identifiable. Other indicators include a relatively constant temperature (no more than 8º F above ambient air temperature even after turning the pile) and a pH close to 7 (neutral).
(Reprinted with kind permission from Ocean Beach People’s Food Co-op; San Diego, CA)