Compost Making 101

One of the best natural fertilizers and soil builders is available free. You make it yourself and solve some environmental problems at the same time. 

It’s compost. Good gardeners have been making their own compost for a long time, but it has recently been “discovered” as one solution to the problem of our shrinking space in landfills. 

Many communities now forbid yard wastes or charge a premium for taking them. Commuunity composting has arrived on the scene, and you can also do it in your own backyard. Leaves, grass clippings, and even vegetable wastes from the kitchen are the stuff compost is made of.

Making compost is simple and inexpensive. It is a little like making a lasagna–a layer of this, a layer of that and then let the whole thing cook until it’s done. 

For equipment, you simply need an open-sided container that will form a bin from three to five feet across and not more than five feet high. The sides need to be open because making compost requires air circulation. 

Some possible bin materials that can be found free or cost very little are: 

  • Stiff welded wire mesh (a nine-foot length three feet high makes a good bin when formed into a circle and wired together at the ends)
  • Concrete blocks with sections of snow fence, or shipping pallets roughly nailed into a three sided box
  • Chicken wire nailed to frame made of 2-by-4s.

The recipe for compost is air plus moisture plus layers of waste materials like leaves, grass clippings, kitchen scraps (not meat or bones), weeds pulled from the garden, and so on.

These things dumped into a bin will decompose slowly over time and that might be all you want.

Real compost, however, is made in a few weeks by constructing a pile that heats up to more than 140 degrees, killing any weed seeds or harmful bacteria in manures.

These piles are made by layering materials high in carbon (leaves, for example), with materials high in nitrogen (manure, alfalfa meal, cottonseed meal).

The classic organic gardener’s recipe for compost calls for a layer of vegetable matter about six inches thick, a layer of manure about two inches thick, then a thin layer of soil with ground limestone added. This compost lasagna is repeated until the pile is three to five feet high. A little depression is made in the top and it is watered. 

Serious composters often have several bins in a row where they collect and stockpile materials in preparation for the day they build a layered compost pile. 

The smaller the pieces, the faster they will be broken down by the many types of bacteria that will go to work. A chipper or grinder is becoming an increasingly important piece of equipment for shredding soft materials for composting. Coarse, woody materials are also chipped and used as mulch on flower beds and around landscape plants.

In about two weeks, the bacteria will have reduced a lot of material in the pile to compost and caused it to heat up, but they probably will have run out of oxygen. The pile now needs to be turned to be aerated.

If you used a wire mesh, you can simply stand on top of the pile and pull it straight up and off. Then set it to one side and turn the pile into it. Depending upon your setup, you can turn the material into an adjacent bin or turn it within the bin itself. A three-side bin makes this easier. 

Commercial compost machines available in garden centers often make this process easier by putting a drum or container on some kind of turning device.   

In another week or two, the compost can be worked into your soil. Any remaining large lumps can be recomposted. Things like broccoli stalks break down faster if they are pounded with a mallet to soften them up.  

There are as many variations on the composting theme as there are gardeners. For example:

  • Keeping a supply of red wiggler earthworms in a container in the
    basement to compost kitchen wastes. 
  • Blending small amounts of vegetable wastes in a blender and adding it
    to houseplants. 
  • Simply burying kitchen wastes in flower or vegetable garden beds. 
  • Vegetable kitchen wastes, including coffee grounds and egg shells-even
    hair, feathers, wood ashes, ground stone and shells-can be composted
    along with yard wastes. Items that should be kept out of compost
    include meat and bones, large amounts of sawdust, pet manure and, of
    course anything metallic or plastic. 

When the compost is done, it can be turned into the soil or sifted through a screen of hardware cloth and used to pot houseplants. Composting is one of the most direct and beneficial forms of recycling around.


Provided by the National Gardening Association.