The Proper Compost Ratio of Greens and Browns

compost pile

The Spruce / Sydney Brown

Composting is a great way to turn your kitchen refuse into fertilizer for your garden. The average household produces more than 200 pounds of kitchen waste every year. Reduce the organic trash you send to the landfill if you can.

If you are new to composting, then there is a way to go about it. You have to feed the pile appropriately to make sure that microorganisms that are breaking down the mix are not overwhelmed and can multiply.

Composting includes a balanced "browns mix" and "greens mix." Here's what greens and browns mean:

  • Greens are materials that are rich in nitrogen or protein. They are also the items that tend to heat a compost pile up because they help the microorganisms in the pile grow and multiply quickly.
  • Browns are carbon or carbohydrate-rich materials. The main job of browns in a compost pile is to be food sources for all of the lovely soil-dwelling organisms that will work with the microbes to break down the contents of your compost pile. Also, brown materials help to add bulk and help allow air to filter through the pile.

All forms of kitchen waste can be composted but you will want to skip composting meat, dairy, and fats. These items will eventually break down but take much longer. However, these items are guaranteed to smell bad and attract flies, rodents, and other unwanted pests. If you truly want to compost your meat scraps, consider fermenting using the Bokashi compost bin system.

Browns for the Compost Pile

Brown materials for composting include dry or woody plant material. In most cases, these materials are brown, or naturally turn brown. Brown items include the following:

  • Fall leaves
  • Pine needles
  • Twigs, chipped tree branches/bark
  • Straw or hay
  • Sawdust
  • Corn stalks
  • Paper (newspaper, writing/printing paper, paper plates, napkins, and coffee filters)
  • Dryer lint
  • Cotton fabric
  • Corrugated cardboard (without waxy/slick coatings)
"browns" for the compost pile

The Spruce / Sydney Brown

Greens for the Compost Pile

Green materials for composting consist mostly of wet or recently growing materials. Green materials are usually green or come from plants that were green at some point. But, this is not always the case. Here are green items:

  • Grass clippings
  • Coffee grounds/tea bags
  • Vegetable and fruit scraps
  • Trimmings from perennial and annual plants
  • Annual weeds that haven't set seed
  • Eggshells
  • Animal manures (cow, horse, sheep, chicken, rabbit, but not dog or cat manure)
  • Seaweed
"greens" for the compost pile

The Spruce / Sydney Brown

The Compost Ratio

You will often see recommendations for an ideal ratio of browns to greens. Generally, a ratio of 3 parts to 4 parts browns to 1 part greens works well, but you do not need to be exact about it.

If you do not get a good mix of brown and green materials, your compost pile may not heat up, may take forever to break down, and could start to stink up your yard. These issues can usually be remedied easily by tweaking the ratio.

If you find that your compost pile is not heating up, then you may need to add more green material to the compost. If you find that your compost pile is starting to smell, you may need to add more browns.

In the end, decomposition happens. It is a natural process. Pile your compostable items, turn them (or not), and in time, you will have compost. It really is that simple.


It's best to regularly turn your compost pile for "hot composting," which optimizes microbial activity. Doing this speeds up the process and exposes bits of browns and greens that aren't fully decomposed to moisture and heat to make them break down.