Composting: What, How, Why?

May 29 marks National Learn About Composting Day. This article explores composting's prehistoric roots, its environmental advantages, and how to begin your own composting practice.

1. What is Composting?

Composting involves recycling organic materials into soil-enriching amendments. Microorganisms—bacteria, fungi, and worms—accelerate this natural process by breaking down organic matter when oxygen, heat, and moisture are present. These microbes require carbon and nitrogen for growth, water for digestion, and oxygen for respiration. "Composting is nature's way of recycling and is one of the most powerful actions we can take to reduce trash in landfills and build healthy soil."

2. When Was Composting Discovered?

Composting practices date back to the Stone Age. Scottish farmers around 5000 BC plowed decomposing organic material into fields, while early American populations developed similar techniques independently. The Akkadian Empire documented compost-making on clay tablets in 2350 BC, marking the first written record. Following the Dark Ages, Renaissance authors like William Shakespeare revived composting knowledge. Early American leaders, particularly George Washington, recognized composting's value and published writings about soil amendments.

3. What Are the Benefits of Composting?

Composting delivers substantial environmental and agricultural benefits:

• Enhanced soil nutrient content and microbial biodiversity
• Improved water retention and drought prevention
• Better stormwater filtration and reduced nutrient runoff
• Prevention of soil erosion and compaction
• Decreased dependence on chemical fertilizers and pesticides
• Higher agricultural crop yields
• Reduced landfill waste and carbon sequestration

4. How Can I Begin Composting?

Choose a Method: Select from open bins, piles, or tumblers based on available space, time commitment, and waste volume.

Select a Location: Choose an accessible year-round spot with good drainage and air circulation.

Gather Materials:

• Green/nitrogen-rich items: food scraps, grass clippings, fresh leaves (store in closed kitchen containers or refrigerator)
• Brown/carbon-rich items: dry leaves, wood chips, cardboard (store outdoors)

Build Your Pile:

1. Start with a 4-6 inch layer of larger browns like twigs for drainage and aeration
2. Alternate green and brown layers
3. Maintain a ratio of at least 2:1 browns to greens

Maintain Your Compost:

• Turn weekly during summer, every three weeks in winter, to improve aeration and reduce odors
• Keep moisture level like a wrung-out sponge; add water if dry, add browns if overly wet

5. What Can I Use My Compost For?

Finished compost appears dark, crumbly, and earthy-smelling—bearing no resemblance to original materials. Use fully decomposed compost only to avoid pest attraction and plant damage.

Application Methods:

• As soil amendment: Mix 2-4 inches into top 6-9 inches of soil
• As mulch: Apply 3-inch layer atop 2-3 inches of loosened soil, away from stems and trunks

Uses:

• Vegetable beds
• Flower beds and containers
• Lawn rejuvenation
• Tree and shrub planting
• Potted plant replenishment
• Weed and pest management