Browns & Greens

A Balanced Diet

Composting will be most rapid if the decomposers are fed a mix of carbon-rich and nitrogen-rich materials, also known as browns and greens.


These high-nitrogen materials decay rapidly, supply nitrogen for composting, and tend to accumulate in spring and summer.

Examples of greens include:

  • Vegetable scraps (12-20:1)
  • Coffee grounds (20:1)
  • Grass clippings (12-25:1)
  • Manure
    • Cow (20:1)
    • Horse (25:1)
    • Poultry (10:1); with litter (13-18:1)
    • Hog (5-7:1)

Since greens foster poor aeration and may have foul odors if composted alone, it is best to mix greens with browns when composting.


These high-carbon materials decay very slowly, can help keep compost piles aerated, and tend to accumulate in the fall.

Examples of browns include:

  • Leaves (30-80:1)
  • Straw (40-100:1)
  • Paper (150-200:1)
  • Sawdust 100-500:1)
  • Animal bedding mixed with manure (30-80:1)

Since browns will tie up nitrogen in the soil if not fully composted, you may need to stockpile browns until they are needed to mix with greens.