The leaves have fallen and Autumn is here so now is the perfect time to try your hand at composting! A common recipe for many is to add fallen leaves, with a bit of food scraps, a touch of yard waste, and a good dose of water. Mix occasionally as compost pile temperatures rise. Set your calendar for 3 weeks to several months as you watch and wait for the emergence of “brown gold,” a wonderfully rich and nutrient-filled compost!

Sounds easy right? Well, before diving too deeply into details, let’s first discuss the basics. Composting is a naturally occurring process in which microorganisms and soil invertebrates chemically and physically break down yard waste, such as leaves and grass clippings into a valuable soil amendment or mulch. Gardeners have used compost for centuries to improve soil structure, fertility, water-holding capacity, aeration, and root development in plants. Plants that benefit from compost include seedlings, potted plants, garden crops, field crops, and landscape trees and shrubs.

Composting occurs naturally, but can be accelerated and improved by controlling environmental factors. To produce compost efficiently several conditions must be met. Microbes such as bacteria and fungi along with worms and insects need oxygen, water, and nitrogen for proper decomposition to take place. Particle size also affects efficiency. The smaller the plant pieces, the more rapidly they will break down. Use a chipper or lawnmower to chop up leaves and small twigs before adding them to the pile.

Mature compost is dark brown or black, crumbly, and has an earthy smell. Locate your compost pile or container close to where it will be used so it won’t interfere with activities in the yard or offend neighbors. Piles work best where it is somewhat protected from drying winds, yet receives partial sunlight for heat. When building your compost pile, think layers! Rich compost is created by layering browns (dead leaves and newspaper) and greens (fresh yard clippings and kitchen scraps) into piles or containers. As you layer, remember to add nitrogen (e.g., fertilizer or manure) and two handfuls of soil along with watering your pile to the point of being moist, but not soggy. Repeat this layering process until the pile reaches a height no greater than 5 ft by 5 ft. Remember microbes thrive best at a Carbon (C) to Nitrogen (N) ratio of 30:1. This means for every 30 parts carbon (brown), add 1 part nitrogen (green).

A finely tuned compost pile will generate heat with temperatures between 130 and 160° Fahrenheit. As the center cools, turn the pile with a pitchfork or shovel to ventilate and help speed decomposition. You will need to do this every three days until the batch is finished. Remember to water your pile if its moisture content reaches below 40-60%.

A well-managed compost pile will be ready in several weeks if diligent in turning the pile every 3 days. It takes several months if you aerate the pile weekly and one year if the pile is left alone.

Avoid composting the following items such as meats, bones, fish, eggs and dairy products, pet feces, plant material treated with pesticides, peanut butter, and cooking oil or animal fats as any of these may attract animals and create smelly odors from your compost.

Compost is ready to use when it has a dark crumbly earthy look crawling with insects and worms. Allow the pile to sit for at least 3 weeks to make sure the decomposition process has stabilized then utilize your finished product as a soil amendment, mulch, in potting mixes, or as compost tea. For more information about the composting process contact the N.C. Cooperative Extension, Macon County Center at 828 349 2046 or email clbreden@ncsu.edu.

Resource Links

NCSU Home and Backyard Composting

NCSU Large Scale Composting

Compost Pile

Compost Thermometer