Composting is the process of microbial decomposition of mixed raw organic materials (kitchen scraps, yard waste, grass clippings, etc.) into humus. Humus is a dark, fluffy material resembling rich soil. It is very beneficial to incorporate humus into garden soil because it improves its overall structure and provides nutrients plants need to prosper.


Composting Essentials

There are four essential ingredients needed in order for a compost pile to break down organic matter to produce humus. The proper balance of carbon and nitrogen is needed for rapid decomposition:

  1. Carbon
    For example, fallen leaves, straw, or corn husks.
  2. Nitrogen
    Material such as fresh grass clippings or fresh manure, if available.
  3. Water
    Keep the contents of your compost pile moist, but not soaking wet. Try creating an indentation in the center of the pile to encourage water to move through the pile instead of running off of it.
  4. Soil
    This provides all the necessary microorganisms for the composting process. A general rule of thumb is to add a sprinkling of soil for every layer of compost that is added.


Starting Your Own Compost Pile

  1. Start the compost pile with a 3 inch layer of coarse plant material that is rich in carbon. This will aid with aeration and drainage and can include things like:
    – small to medium-sized twigs
    – chopped corn stalks
  2. On top of this, put a layer of plant and kitchen refuse. This can include things like:
    – leaves
    – weeds
    – waste from garden plants
    – coffee grounds
    – crushed egg shells
    – canning wastes
    – kitchen scraps
    – AVOID meat wastes as this can attract digging animals
  3. Next, add a layer of nitrogen-rich material, such as:
    – fresh grass clippings (not too thick a layer, as they will mat)
    – fresh manure, if available
  4. Turn over the pile periodically
    The pile should be forked over after about a month (2 weeks if the material is shredded). The goal of forking over a pile is to put the outside materials on the inside and vice versa. Turn the pile again in 5 to 6 weeks.


Finished Compost

Plant material should decompose into good compost in about 4 or 5 months in warm weather, but may take longer under cool or dry conditions. Composting may be completed in 1 or 2 months if the materials are shredded, kept moist, and turned several times to provide good aeration.

When compost is finished, it will be black and crumbly, like good soil, with a pleasant, earthy smell.

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