Compost: What to Do If…
During autumn, master gardeners often write an article about “leaving the leaves.” Using your fallen leaves creates compost or mulch on-site, reduces the waste stream, and prevents air pollution from burning. So, I was caught off guard when a knowledgeable gardening friend asked, “What do I do if I don’t have enough browns for my compost pile?” What if you don’t have enough materials of either kind to create a fast-acting compost pile?
First of all, don’t be too concerned about the recipe or ratio in your compost. Grass clippings, leaves, pine needles, spent garden trimmings will break down if left long enough. Piles of leaves create a lovely leaf “mold” in about a year. Composting is simply our human way of speeding up nature’s process.
Brown materials refer to high-carbon containing substances that fuel the metabolic processes of microorganisms. Think of them as “dry materials.” Easy to identify by being dry to the touch, they often appear brown in color. At this time of year, browns should be easy to find.
Native oak leaves are an excellent base for compost, containing nutrients created by the tree and inoculated with naturally-occurring yeasts, bacteria, and fungi. Pine needles are plentiful at higher elevations and provide natural air spaces when piled together. They do take longer to break down, but patience produces compost from pine needles.
If tree trimmers have been working in your neighborhood, ask them to drop some of their shredded woody material in your driveway. It may take wheelbarrow trips to move it to your compost area, but it provides a satisfactory base for composting.
Neighbors may have fallen leaves that will be removed by their yard maintenance service. If the trees haven’t been sprayed with pesticide, ask if you can cart away some bags or wheelbarrows of leaves.
Other sources of brown material include sawdust (without glue), newspapers, cardboard, straw and piles of dried weeds (without mature seeds). Most dry materials, especially cardboard, tree and shrub trimmings, and large leaves should be chopped into smaller pieces to allow them to decompose faster. Leaves can be chopped with a shovel, run over by a lawn mower, or shredded by using a weed trimmer in a garbage can. If you don’t have a chipper-shredder, small branches can be piled until the leaves fall off and branches can be broken into smaller pieces.
What if you have lots of naturally-occurring dry materials, but not enough greens? “Green” refers to nitrogen-containing materials that microorganisms use to create their DNA, amino acids and proteins.
Kitchen scraps, used coffee grounds and tea bags, grass clippings and animal manures are excellent sources of nitrogen. Horse and cow manure, llama and goat droppings can often be procured from friends and neighbors, if you don’t have animals. One of my favorites is chicken bedding. A sure-fire addition to compost (be sure to let it break down entirely, so it’s not too “hot”), it’s a ready-made combination of wood shavings (brown) and chicken manure (green). Green materials, since they are high in moisture, do not need to be broken down into smaller sizes. The wonder comes from watching them disappear in your compost pile.
In this season of falling leaves and dying garden annuals, enjoy the bounty that nature continues to provide as it creates compost to feed next year’s green growth.
Rebecca Miller-Cripps is a UCCE Master Gardener of Tuolumne County.