Creating and applying compost is the very best thing a gardener can do for the garden.
Composting is the natural process by which organic materials are broken down, making them available to plants and microorganisms. It is a major component of pedogenesis, or soil creation. Without healthy soil, we begin to lose our food, water and air. Yeah, it’s kind of important.
More benefits of composting:
One of the nicest things about composting is that bacteria and fungi do most of the work for you! Other organisms, such as worms and insects, also pitch in to help. Now, it is possible to simply dump everything in a pile and wait for nature to takes its course. Eventually, there would probably be a nutrient rich soil amendment, but it might take years. It might also turn into a stinky, rotten mess. Follow these tips for successful composting in a reasonable amount of time.
Selecting a site for composting
Understand the process: Organic matter + air + water = compost
Organic matter* consists of yard and kitchen waste that has been cut into 2” or smaller sized pieces. Smaller pieces compost faster because there is more surface area for decomposers to reach. Organic matter is considered either “green” or “brown”. Green matter includes cut grass, pulled weeds, kitchen scraps and manure, and it is rich in nitrogen. Brown matter is rich in carbon and includes dried leaves, straw, and shredded newspaper. The ratio of green to brown is a major factor in how long it takes a compost pile to breakdown. “Hot” piles work fastest and use a 30:1 carbon-to-nitrogen ratio, while slower piles can have a 2:1 carbon-to-nitrogen ratio. If material is continually added to a single pile, it will slow the process. A better choice is to have 2 or 3 piles, at various stages of decomposition.
Decomposition is an aerobic process, which means it needs air. Air helps breakdown organic matter and those tiny workers need it, too! Air enters a compost pile by turning it every few days. [Read: good exercise]
Water is needed for the same reasons as air: it aids in decomposition and it keeps microorganisms and other decomposers alive. Keep the compost as damp as a wrung out sponge and avoid simply watering the top, as this tends to cause runoff. Watering as the piles are turned works the best. If the pile gets too wet, spread it out and let it dry, or it will rot
Temperature is another composting factor. As materials break down, especially the green ones, energy is released in the form of heat. If you’ve ever watched a big pile of freshly cut grass, you know exactly what I mean. Under the right conditions, a pile of grass clippings can burst into flames! (And it stinks to high heaven). Ideally, the right conditions will generate temperatures between 122 - 131 degrees Fahrenheit. If temperatures remain above 140 for at least 10 days, weed seeds and pathogens will be killed. If temperatures stay above 160, however, decomposers will die and the process will stop. Some people take their composting very seriously and monitor temperature. I don’t.
Because temperature is a factor, do not expect much out of a compost pile in winter. Material can still be added, or another pile started. In spring, the whole process will begin again. Also, if a area is especially hot or wet, cover the compost pile to maintain desirable moisture levels.
Compost is called “finished” when it is ready to use. Finished compost takes up 25-40% of the original occupied space, depending on its ingredients. Compost can be dug into beds before planting, a 2” layer can be applied over lawns as an amendment, or it can be used as mulch. Personally, I also add compost to the bottom of potted plants before adding high quality potting soil and my plants seem to like it a lot.
For those who do not have space for a compost pile, bin, or drum, try composting with worms! This is called vermiculture. Worm bins can compost an amazing amount of yard and kitchen scraps pretty quickly. Worms can eat their body weight in scraps every single day! Learn how to build worm bins and compost with worms at the UC Agriculture and Natural Resources page about worms.
Remember, composting is easy and it provides a powerful boost to the garden. Start composting today!
*Most recommendations warn against using meat, dairy, and grease in compost piles. Other people have no problems with it. Personally, I use the majority of my kitchen “waste” to make soup stock. The solids are then fed to my chickens. Whatever they don’t eat (along with what they did eat) ends up in the compost pile, bones and all. I have had no problems and my plants seem to appreciate the calcium.
You can grow a surprising amount of food in your own yard. Ask me how!