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
sides.
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.
First pile a layer of 6-8"
of organic materials, then add a layer of 1-2" nitrogen rich material,
such as farm manure, (no pig manure) or 10-6-4 fertilizer. Then add good
soil or old humus. Repeat the process until the bin is full. You don't
need special compost activators or starters when soil, old compost or
fertilizers are used.
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.
MOISTURE
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.
TEMPERATURE
Proper temperature
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.
COMPOSTING TIME
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.
CLIMATE
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.
TURNING
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.
Compost Uses
PROBLEM?
Composting requires
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
Wet material
Too much fresh fruit skins,
rinds, bruised fruit or vegetables.
Solution: Add shovel
full of dry soil, shredded leaves or newspaper.
Soggy material
Rain or excessive watering.
Solution: Turn pile
to aerate and add shredded leaves or newspaper.
B. PILE DOESN'T SMELL
Moist material
Not enough nitrogen material.
Solution: Add nitrogen
materials like grass cutting, manure or an organic activator.
Dry material
In direct sun and no new materials
added.
Solution: Add enough
water to dampen only and add nitrogen material if necessary.
