Compost to Reduce Yard Waste and to Use As a Soil Amendment
(Excerpted from Ecoscaping Back to the Future…Restoring Chesapeake Landscapes, by Zora Lathan and Thistle A. Cone.)
Composting is the natural process of decomposition and recycling of organic material. Nature’s recycling system is efficient, completing the cycle-of-life process. Leaves that fall to the forest floor form a moist mulch layer that protects the roots of plants and provides a home for nature’s recyclers—bacteria, insects, and worms that feed on the mulch, turning it into compost. As the mulch decomposes, nutrients essential to plant growth are released into the soil and are absorbed through plant roots.
Compost contributes to good soil structure, which allows soil to retain nutrients, moisture, and oxygen for long periods of time. When we remove yard waste from the landscape where it was produced, we deprive plants of their own natural fertilizing source. Like the natural composting process in the forest, we can create compost in our yards and gardens by placing yard waste in a suitable spot in bins or piles.
Yard waste alone accounts for approximately 18 to 20 percent of municipal solid waste, and during peak seasons, can account for 25 to 50 percent (US Environmental Protection Agency). Backyard composting saves valuable landfill space. It also saves taxpayers the additional costs to collect, haul, and manage yard waste.
Compost…It’s Habitat Forming!
Composting is nature’s way of recycling organic material. It is a great way to recycle nutrients from our garden clippings, autumn leaves, and other organic materials and to re-use them by making a valuable soil amendment. Compost is often referred to by gardeners as “black gold.” By shredding and mixing grass clippings, plant stalks, leaves, twigs, and (where appropriate) kitchen scraps, the rate of decomposition can be increased. Materials that attract pests (such as meat and fat), promote disease (such as pet waste), promote weeds (weed seeds and roots), cause odors, or create other nuisances should not be composted.
Adding yard waste to a compost pile is more convenient than bagging and dragging leaves and grass to the roadside curb. Why throw away, then go and buy a resource you have right in your own backyard? Usually the most accessible items to add to a compost pile or bin are leaves, shredded cardboard or newspaper (black and white only), sawdust, straw, twigs and other woody materials, which are examples of carbon-rich or “brown” material; while fresh grass and garden clippings, fruit and vegetable scraps, and coffee grounds and filters are nitrogen-rich “green” material. An easy formula to remember is: “One part green, two parts brown*, makes the yard waste turn to ground. Add some water and some soil, turning is the only toil.” (*Proportions may vary.)
If you are trying to be very scientific about composting, and make usable compost in the quickest, most efficient manner, then you can try to mix the optimum amounts of carbon and nitrogen in your compost. About 30 to 1 respectively, by weight, works best. The 30:1 ratio of C:N is an ideal rule of thumb, but should not cause excessive concern. You can look up the exact C to N ratio of different substances you add to compost, as well as suggested recipes for compost piles on the Internet; or just add what you have, and it will probably work pretty well! Just make sure you have some green and some brown; and try adding a bit of compost or soil to introduce those hard-working microbes; and add water as needed.
Factors to keep in mind:
- Locate your compost bin or pile in an appropriate area, as close to where it will be used as possible, without being in the way.
- Shredding yard waste hastens decay.
- Nitrogen, e.g., fresh grass clippings, accelerates decomposition, although too much nitrogen can cause odors.
- Air: The pile or bin should be well ventilated. Turning the pile speeds up the decomposition process.
- Water: The compost pile should be kept as moist as a squeezed sponge. The bin or pile should be at least 3 feet square to ensure enough heat build up. Temperatures of 160 degrees and above will kill most weeds seeds. However, if your pile is very large, it may become difficult to turn.
Anaerobic (without oxygen) composting can work too, if you don’t turn or aerate your compost; but it works more slowly and can also generate odors.
There are varieties of bins from which to choose. Some bins can be ordered or purchased from local garden supply retailers, or homeowners can construct their own from cedar, other wood, or recycled wooden pallets. There are also special in-ground bins which are animal resistant and are good for food waste. Another option is a simple compost pile. Even if you don’t mix organic material in certain ratios, and don’t turn or add water to the pile, it will eventually break down into a rich soil amendment.
Composting Resources
▪Anne Arundel County Yard Waste and Composting Program
▪Maryland Cooperative Extension Services’ Backyard Composting Brochure