What is compost?

Compost is that dark, crumbly, earthy-smelling form of decomposing organic matter. It is the end result of the decomposition of organic material by organisms in the soil.

Why compost?

Compost contains essential plant nutrients. It improves soil structure. It retains water, decreases runoff and feeds beneficial soil organisms.

Easy steps to composting

Identify location

  • Decide if you want an open pile or an enclosed bin.
  • Find a convenient location with well-drained soil.
  • Avoid placing the pile or bin against wooden structures; the decomposers contribute to wood rot.

Build and maintain pile

  • Start with a bottom layer of browns (or a bin full of dry leaves).
  • As you add kitchen or garden waste to your compost, keep the pile moist but not wet or dry.
  • Aerate the pile by turning it occasionally. Chop materials into pieces 1-inch or smaller to hasten the composting process.
  • Try to keep a balance of browns and greens, with a layer of brown on top.
  • Cover the pile.

Make-it-fast/hot composting

  • Build a pile with a minimum of 1 cubic yard of material (equal parts browns and greens) to generate heat.
  • Don't add to the pile but keep it as moist as a wrung-out sponge. Turn it about once a week.
  • The process is complete when the material no longer heats up when turned, about four to six weeks.
  • Allow the material to age an additional four to six weeks before using it.

Finished compost

The compost will be dark and crumbly and look like soil. Individual materials will not be recognizable. It will smell fresh and earthy.


Smells bad or is too wet

Problem: Not enough air or too much moisture.

Solution: Turn and add dry brown materials.

Pile is too dry

Problem: Not enough water and too much brown.

Solution: Turn and moisten.

Pests around bin (dogs and/or rodents)

  • Problem: Unsuitable materials in pile (see 'What not to compost' list)
    • Solution: Avoid meat, dairy and fatty foods. Bury food waste in pile.
  • Problem: Pile is an attractive nesting place for rodents.
    • Solution: Consider using a rodent-proof bin.

Files and insects

Problem: Food waste on top.

Solution: Bury food and keep covered with browns.

Pile not breaking down fast enough

Problem: Pile is too small. Not enough green material.

Solution: Make pile at least 1 cubic yard. Maintain equal browns and greens.

Additional compost methods

In-place composting

Simply bury organic material at least 12" deep in garden soil, rotating locations.

Sheet mulch composting

An excellent way to create, enlarge or restore garden beds by layering green and brown organic materials directly on the garden area.

Trench composting

A method using fall leaves on your garden paths to make compost over the winter.

Composting with worms

Worms do the work of converting vegetable scraps to compost.

What to compost


  • Grass clippings
  • Small prunings
  • Flowers
  • Tea and coffee grounds
  • Veggie and fruit waste
  • Aged manures


  • Leaves
  • Dried flowers
  • Straw
  • Sawdust
  • Shredded paper

What NOT to compost

  • Meat
  • Oil
  • Dairy
  • Pet or human waste
  • Invasive or diseased plants
  • Pressure-treated wood
  • Wood ash

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