You may be surprised to learn that many of your Washington Grove neighbors are composting their autumn leaves, yard trim and food scraps. Rather than sending these valuable materials to landfills, they are putting them to much better use — while also helping to reduce climate change. If you would like to learn more, read on.
What is Composting?
Composting is the natural degradation (by bacteria, protozoa, and fungi) of vegetation, such as yard scraps, leaves, wood chips, straw, grass clippings, and food scraps, in the presence of oxygen (in air) and water. Over time, composting generates a pleasant-smelling, rich source of soil enhancer that can be used to promote healthy plant growth in your garden.
Why Compost?
Montgomery County residents and commercial operations, such as restaurants and food markets, together produce nearly 150,000 tons of yard trim and food scraps each year. When yard and garden vegetation and food scraps are transferred to landfills, these organic materials will degrade. But vegetation and food buried under piles of refuse in landfills degrades in the absence of oxygen and produces methane, a greenhouse gas that is a major contributor to global warming. Properly composted yard, garden, and food materials, however, will sequester carbon and produce a valuable soil supplement that can be used to enrich one’s garden and enhance plant growth.
How to Compost
Composting requires only four basic components: air, water, and a suitable balance of brown materials (rich in carbon), such as autumn leaves, wood chips, shredded paper, and cardboard, together with green materials (rich in nitrogen), such as green leaves, grass and flower clippings, coffee grounds, fruit and vegetable scraps, and horse or cow manure. Some things should not be composted at home: meats, cheeses, and fatty foods. A more complete list of materials to include and exclude in your compost, and why, are listed at U.S. EPA’s Composting at Home web page.
The addition of green materials speeds the decomposition of brown materials; but without adding sufficient brown materials, greens decompose too quickly into foul-smelling materials. A ratio of approximately 2-to-1 brown-to-green materials usually works well. Add water, if needed, to keep the mixture just slightly moist (“like a wrung-out sponge”). Turning the compost by hand every few weeks provides the needed aeration.
Complete degradation, to a dark, rich, earth-like-smelling product, usually takes several months or more. Starting a batch in the early spring will often produce compost you can use to enrich your garden in the late fall. The time required depends on several factors:
- Too much brown and too little green material slows the process;
- Starting with finer materials (shredded paper, smaller pieces of fruit and vegetables, mulched leaves) speeds degradation; and
- Placing the compost where it receives warmth from the sun accelerates the process.
- The process might also be accelerated by use of compost starter or asking for a shovelful of active compost from a neighbor’s pile; even adding in a shovelful of soil will introduce trillions of microbes to the pile.
When organic materials are properly composting, they also produce their own heat (100° -140° F) especially during the first few weeks, which render weed seeds and pathogens inactive. Compost thermometers are widely available for about $20 (or ask a neighbor if you can borrow theirs).
Yard Trim Composting
To compost yard trim, such as leaves and grass clippings, in your garden, find a level, well-drained location for either an open compost pile or a place to set a simple wooden container that allows sufficient aeration. Montgomery County offers free, 17.6 cu ft composting bins to residents; learn where to pick one up.
Food Scrap Composting
Yard trim and food scraps are commonly composted together. To address possible concerns about food scraps attracting rodents and other pests, Montgomery County’s guidance is to compost them (together with brown materials) in rodent-proof bins.If you decide to use food scraps in an open compost bin — or even in a closed one — here is some best practice advice. Do not include meat, cheeses, and fatty foods, as noted above. Bury fruit, vegetable and herb scraps in the pile, not on the surface. Leaf tea and tea bags are just another leaf and are fine for the pile. And coffee grounds are a green (nitrogen-rich) material that is a mild pest repellent. If you ask local coffee shops for their used grounds, they are usually happy to give them away; the coffee filter paper is also good for the compost pile. Monitor your bin for rodent activity and make changes if needed — don’t become a pest to your neighbors!
Rodent-proof bins can be constructed by homeowners or purchased online. Commercially available bins for food composting at home are available for purchase from various vendors, including rotating bins that facilitate aeration. Prices vary from $50 to $300, or more, depending on bin capacity and design. Montgomery County has tested two designs of rodent-proof bins that it recommends. These are free to residents of Montgomery County who have recycling service provided by the county.
Homeowners also can subscribe to a weekly pickup service of food scraps from local commercial composting services. Two composting pickup companies that service our area are Compost Crew and Key Compost. These services typically charge about $30/month, but offer substantial cost reductions to groups of neighbors, towns, and communities that sign up for their service.
Another option for composting food scraps is to deposit it at a free composting drop-off site nearby in Gaithersburg.
There is also a free drop-off site at MOM’s Organic Market in Rockville, next to their electric vehicle charging stations.