The most important thing for you to know about composting is that everything composts. Eventually. The peels from the cucumbers added to your dinner salad and the outside leaves of your lettuce. The cardboard roll from the inside of your toilet paper and the hair your drain net caught before it plugged your sewer line. Seaweed you collect from the seashore and weeds pulled from your lawn. Old newspapers. A 1971 Volkswagen Beetle. OK, that last one might take a little longer than you want and maybe you don't fancy tires, fenders, oil and gasoline in your garden anyway. Then again, maybe you do -- as a unique planter! Remember it's your garden.
Sir Albert Howard is sometimes called the father of the organic farming movement. He is certainly the father of the modern composting movement. Sir Albert created detailed methods and specifications for mixing vegetable and animal wastes to create a rich humus that would return fertility to the soil. "Why bother with returning fertility to the soil," you ask? Because growing specific crops season after season for human (or animal) consumption tends to leech the productivity out of the soil. Sir Albert's magnum opus on composting or the Indore Method he called it, "An Agricultural Testament", is available online or in hardback from Amazon.
I am a little more partial to the methods of the Japanese organic farming guru, Masanobu Fukuoka and his "do nothing" methods. Fukuoka's masterpiece, "One Straw Revolution", is also available online. Fukuoka's methods involve observing nature and doing your best to let nature take care of all the food production in your farm or garden. Masanobu chides us that do nothing farming does not mean that you can lie in bed all day. His philosophy is simply that we should look first to the methods by which nature produces her abundance and to the extent possible try to piggyback our efforts on the direction that nature is already taking anyway. He has some very interesting ideas about weeds!
Fukuoka talks about growing rice, which we are not going to be doing in Santa Monica. But we can borrow on his method of leaving the rice straw right in the field where it grew after the rice grains are harvested. We don't have to build a big pile or dig a deep trench to make compost. We simply cover our gardens with our refuse, taking reasonable care to mix layers of nitrogen rich elements (greens such as kitchen waste, grass clippings or seaweed) with layers of carbon rich elements (browns such as shredded paper, dried leaves or wood chips). A cornucopia of bugs from bacteria to beetles (not the Volkswagen variety) to worms chomps on the compost raw material to turn it into a form that our plants can use for nutrition -- humus. Keep an eye out for things like rats. I had to start burying my compost when the local rats figured out where to find watermelon rinds.
Building your soil with the Fukuoka method has a number of advantages over the typical spade or rototill methods used in America. First, it's a lot less back breaking. No hard digging, lifting and turning. Second, it leaves the nutrients in the soil rather than exposing them to oxygen where they burn away quickly. Third, it leaves years worth of ancient weed seeds undisturbed under layers of soil rather than stirring them up and causing them to germinate. And it kills most weeds by burying them from the sunshine they need to flourish. Finally it creates a soil with structure -- a soil that has aeration. Plant roots need air as well as soil and water to thrive. Of course in order to maintain this aerated structure you need to refrain from walking on your soil. But this is easily accomplished by designing your garden with a path and bed layout.
Good food is the foundation of a good life. Healthy plants are the foundation of good food. Good soil is the foundation of healthy plants. Compost is a critical component of good soil. And pretty much everything in your house that is not some kind of toxic chemical is potentially a component of good compost. There are at least 163 things you can compost and better the stuff ends up right in your backyard (or front yard) garden than to be hauled away to a landfill who knows how many hundreds of miles away.
As with so many things in the garden, there is no need to worry about perfect compost. Just get the composting started. Then observe and adjust.