WHY SHOULD WE COMPOST
Compost contains valuable nutrients that could replace or supplement use of commercial fertilizers by homeowners.
Proper home composting of organic garden wastes can reduce air pollution, reduce the volumes at the landfill or incinerator.
Volunteer home composting is the most cost effective method of dealing with the yard and compostable kitchen waste.
Many organic materials
which you may have been burning or throwing in the garbage is recyclable
by composting. Composting being the most efficient way to divert organic
wastes from our county's solid waste stream.
WHAT MATERIALS MAY BE COMPOSTED?
Do Not Compost
Locate the compost pile or bin in an inconspicuous location. A shaded area is preferred. Place it close to water since the decomposition needs moisture. Don't locate compost piles under trees, because tree roots will invade a compost pile rapidly in the lower layers.
SIZE OF THE COMPOST PILE
The size of a pile needed may vary greatly with the amount of material available. A good size is 4 by 4 feet and 5 feet high. A minimum of 3 by 3 feet and 4 feet high is necessary to reach the high temperature of 150o. These high temperature is a requirement for the composting process, and is needed for killing weed seeds and disease bacteria. You can add small quantities if you can't generate two cubic feet of materials at one time; it just takes a little longer to break down into compost. Although it is possible to stack the compost in a loose pile, decomposition is more efficient in a contained bin or enclosure. The sides should be open enough to provide some air movement through them. One side should open for turning and removal of the compost.
Many types of materials can
be used for building enclosures. Scrap lumber, woven wire fencing, chicken
wire, cement blocks are all possibilities. Some wire fencing is too loose
to contain smaller materials. Line the inside with some plastic (containing
some aeration holes). Pile bricks or concrete blocks without mortar. Leave
space between some of them to allow adequate air movement through the
STARTING A COMPOST PILE
Starting the compost
pile is usually described in terms of layers. Layering provides the quickest
and most complete decomposition. The pile may be started directly on the
ground. However, you need to provide aeration to the bottom of the pile
and drainage. Dig a trench across the base of the area and cover with
a stiff wire mesh before starting the layers. Begin the pile by spreading
a layer of coarse organic material over the area.
SHREDDING OR GRINDING
Shredded or chopped materials decompose the fastest. If a shredder is available, then shred coarse organic matter. Some materials such as leaves and grass clippings tend to mat. Place these in layers only 2" to 3" thick. Better to shred or chop this materials in small pieces.
Moisten, but do not soak the layer of organic material. Over the layer of plant material, sprinkle a high nitrogen source. Some sources are: bloodmeal, cottonseed meal, kelp meal or parts of leguminous plants like clover, vetch or alfalfa. Substitute a 1-2" layer of fresh farm animal or poultry manure if it is available. A complete garden fertilizer, such as 10-10-10 may also be used to supply the nitrogen. One cup for each 25 square feet of top surface area should be adequate.
Next add a layer of soil or sod 1-2" thick. The soil contains microorganisms that help to start the decomposition process. Use a layer of finished compost if there is not an adequate source of topsoil. Continue to alternate the layers of organic materials, fertilizer or farm manure, and soil. The maximum height is about 5 feet. Air is needed, so do not compact the layers. Water each layer as it is added.
The compost pile must be kept moist for proper heating and decomposition. Too much moisture will bring the composting process to an anaerobic condition, which has an offensive smell. A moisture content from 50% to 75% is recommended for composting in the open air.
It may be necessary to sprinkle
the compost if the material is getting too dry. Covering the compost pile
with black plastic keeps the moisture loss to a minimum, and helps the
moisture loss to a minimum, and helps the decomposition during extremely
dry periods. The plastic covering also protects the pile from becoming
too wet during periods of heavy rainfall.
is a very important factor. Much heat energy is released by microorganisms
as decay occurs. Check the temperature with a thermometer, if available.
The experienced composter usually checks the temperature by putting his
hand 8 inches deep in the pile. The compost should feel too warm to hold
your hand for more than a few seconds in the pile. The temperature of
150oF is needed for killing many of the pathogenic diseases and weed seeds.
Failure to reach this temperature might be caused by too much water, improper
aeration, too little nitrogen or too small a pile.
Hasten the decomposition by turning the pile regularly. This will help aeration of the pile and reverse any undesirable reactions.
Complete composting can be
achieved in about 1 month if the materials are finely shredded and turned
at 2 days intervals. Turning the pile monthly will produce compost in
about 6 months. The pile should be turned immediately if at any time a
strong ammonia or other offensive odor is released. During the decomposition
the pile will shrink to about half of its original height. The time needed
for decomposition will also vary with the size of the pile and the season
of the year.
Because the winter
climate in Western Washington is mild, the process of decomposition will
continue in fall and winter, but usually at a slower pace. The pile should
be made a little larger at winter times.
To maintain the temperature, turn the pile regularly. The wetter the pile, the more frequent the turning should be. If the moisture content seems dry, add water. If adequate space is available, it may be easier to have two bins. Turning can than be done by shifting the entire pile into another bin, and later moved back again. The main objective of turning is to shift materials from the outer parts of the pile closer to the center, where they are better able to heat to the 150oF temperature. This temperature is needed for killing many of the pathogenic diseases and weed seeds. A 150oF temperature, will be reached in the center of the pile by the about the third day after starting the pile.
WHEN TO USE COMPOST
Compost is ready for use when the temperature in the compost pile drops to the temperature of the surrounding air. The developed compost should be a fine crumbly, dark mixture. The pH is usually around 7.5. It should have an earthly smell. You can use compost as soon as it becomes ready. Compost stacked in a pile for later use may loose some of the nutrients through leaching. Old compost is still a good soil conditioner even if some leaching out of the nutrients occurred.
about two cubic feet of equal portions of grass, leaves, plant and vegetable
trimmings, all chopped up, moistened and thoroughly mixed to cause the
pile to heat. The outside air temperature must be at least 10oC or 50oF.
It usually takes 3 to 4 days to heat up to a maximum temperature.
A. PILE SMELLS
Too much fresh fruit skins, rinds, bruised fruit or vegetables.
Solution: Add shovel full of dry soil, shredded leaves or newspaper.
Rain or excessive watering.
Solution: Turn pile
to aerate and add shredded leaves or newspaper.
B. PILE DOESN'T SMELL
Not enough nitrogen material.
Solution: Add nitrogen materials like grass cutting, manure or an organic activator.
In direct sun and no new materials added.
Solution: Add enough
water to dampen only and add nitrogen material if necessary.
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