Building Your Compost Pile

What are we really doing?

Put a pile of leaves, a cardboard box and a watermelon in your back yard, exposed to the elements, and they will eventually decompose. How long each takes to break down depends on a number of factors:

  • What are the materials made of
  • How much surface area is exposed
  • The availability of moisture and air

Backyard composting is a process designed to speed up the breakdown or decomposing of organic materials. Let’s take a closer look at how we manipulate the process and speed things up.

We insure the makeup of the material is a mixture that bacteria and other microorganisms can easily feed upon, breaking them down into compost. A proper C:N ratio is the goal. Carbon in fallen leaves or woodier wastes serve as an energy source. Nitrogen in the greener materials provides microbes with the raw element of proteins to build their bodies.

The more surface area the microorganisms have to work on, the faster the materials will decompose. It's like a block of ice in the sun: slow to melt when it is large, but melting very quickly when broken into smaller pieces. Chopping your garden wastes with a shovel or a machete, or running them through a shredding machine or lawnmower will increase their surface area, thus speeding up your composting.

All life on Earth needs a certain amount of water and air to sustain itself. The microbes in the compost pile are no different. They function best when the compost materials are about as moist as a wrung out sponge and are provided with many air passages for aerobic breakdown. Adding water and turning the pile maintains efficient decomposition. Extremes of sun, wind, or rain can adversely affect this balance in your pile.

Understanding these key factors when composting allows for efficient, quick break down of kitchen and yard wastes, turning them into “Black Gold” ¾ compost!

Things to consider when getting started

Location

Where should you place your compost pile? This seemingly simple question must be thought through carefully if you are striving for efficient composting. Remember a pile of leaves will eventually break down, but our goal is to speed this process up. First, find out if your community has any local regulations pertaining to composting. Your municipality may have a setback ordinance requiring composting bins be located a certain distance from lot lines.

The right location is important for a successful compost pile. Choose a level area with good drainage. Standing water will slow down the pile. If possible avoid direct sunlight and areas exposed to strong winds, which can dry and cool the pile. A half day sun situation is ideal. A shaded area is fine but pay attention to limited rainfall through a canopy of leaves, and slow drying out of a saturated pile. Some trees may send roots up into the pile in search of water and nutrients. When the pile is turned, these roots may be damaged. If your only location is near trees, you may want to consider setting a brick or stone foundation.

Select a convenient location. One that is easy to get to and not where you will have to trudge a long distance just to add your carrot peelings. Choose an area that does not interfere with family activities but is close to a water source and has enough space for temporary storage of excess organic wastes. Avoid placing your compost pile near dog areas or other animals. Animal urine and feces may harbor unwanted pathogens.

Don't place your pile directly against wooden buildings, fences or trees, because wood in contact with compost will decay. Avoid placing under a wide overhang that would limit rainfall, or under a drippy eave or rainspout that would continually saturate your pile.

And one final point. Your compost pile may be a thing of beauty to you but not to your neighbors! For some this may not be an issue, but for those who live in higher population areas, this may be something to think about.

Camoflaging a compost pile can be done in many creative ways. Surrounding the pile with tall flowers or plants or using a vine trellis are just a few examples of how to blend a compost pile into its surroundings.

Size

The recommended size for a home compost pile is no smaller than 3 feet X 3 feet X 3 feet, and no larger than 5 feet X 5 feet X 5 feet. A smaller pile may not heat up high enough for efficient breakdown, or it may loose heat and quickly slow down the process. A larger pile may hold too much water not allowing air into the center. This would create an anaerobic environment. Air naturally penetrates 18 to 24 inches into a pile from all directions. The biggest problem with a large pile is physically turning the pile. It can be too much for some people to manage.

When to Start

You can start a compost pile any time of the year, but there are limitations during certain seasons. You can build your pile as materials become available. In the spring and early summer, high nitrogen materials are available, but very little carbon materials are available unless you stored leaves from the fall. In summer you start to have garden debris, but your mowing may be lessened due to high summer temperatures. Fall is the time of year when both nitrogen from cool season lawn mowing and carbon from fallen leaves are readily available.

Tools

Besides the type of bin you use - if any at all - there are a few tools that will make your composting easier. A 4- or 5-tined pitch fork for turning your pile is the main item. You will see compost turners advertised in catalogues, and they do work especially for those who lack upper body strength or have back problems. A garden hose or watering can needs to be handy to water your pile.

Other items you may find useful: Pruners, a machete or a shredder to cut up large pieces of organic waste to increase surface area.

A compost thermometer to monitor your pile’s temperature. A metal pole will also indicate heat. Insert the pole into the center of the pile as you would a compost thermometer. Where the thermometer will tell you exactly the temperature of the pile, a warm/hot to the touch metal pole will also indicate activity.

For kitchen scraps it is a good idea to keep a covered container in the kitchen to store scraps until you have time to take it to the pile. Often it is impractical to run out and dump every kitchen scrap as it is produced. Place the container under the sink or near the back door.

Starting Your Compost Pile

Layering

When starting a compost pile the recommended practice is to layer the materials thinly and uniformly, the same way lasagna is made with thin layers of pasta, cheese, and sauce. Never overdoing any one single ingredient and never skipping a layer in the construction process will prove successful! You only have to layer when starting a new pile. Once the pile is active you add materials by either burying them in the center or incorporating them when you turn your pile.

It is recommended to start your pile on bare ground. Don't place your pile on asphalt or concrete. This impedes aeration and inhibits microbial contact with the earth. If tree roots are a problem, a loosely laid brick foundation could be installed. Placing a pallet underneath the pile is a possibility if you feel the area may be damp or holds water in the spring. This creates air channels from below. Starting with the bottom layer (layer #1), continue to layer until you reach the top or (what happens most often) you run out of material. Firm and lightly water each layer as it is added but do not compact.

Layer 1- The organic materials layer can be vegetable wastes, sod, grass clippings, leaves, hay, straw, chopped corncobs, corn stalks, untreated sawdust, twigs less than ½ inch in diameter, or garden debris. Remember the proper C:N ratio and mix accordingly. Your bulkier organic materials do best in the first ground level layer. As your pile settles, these items tend to allow for more air spaces. Shred or chop up materials for greater surface area. The organic layers should be between 6-8 inches thick. Materials that tend to mat such as grass clippings should be either mixed in or placed in 2-3 inch layers within this 6-8 inch layer.

Layer 2 - Animal manures, fertilizers or starters serve as activators that accelerate the ignition or initial heating of your pile. They all provide a nitrogen source for the microbial community. Some provide proteins and enzymes. If manure from a grain eating animal is available, add 1-2 inch layer. If this is not available, add one cup of 10-10-10 or 12-12-12 commercial fertilizer per 25 square feet. If using a commercial starter, follow label directions.

Layer 3 - Top soil or active compost introduce microorganisms. Plain garden soil is fine. Avoid soil that has been treated with insecticides recently and sterile potting soils which lack these necessary microbes. A one to two inch layer is enough.

Care

Temperature plays an important role in the composting process. Decomposition occurs most rapidly between 110° to 160°F. Within two weeks, a properly made compost pile will reach these temperatures. At this time, you will notice your pile settling which is a good sign that the pile is working properly. Now you must decide how you want to compost. Do you want to add to your pile or just let it continue as is?

If you want to add to your pile, you can do so throughout the growing season and into the winter months. As you add fresh material, you will need to turn and water your pile more often. Monitoring the temperature and turning whenever the piles temperature dips below 110°F keeps your pile active at its highest level, and you will have the fastest breakdown. This means turning the pile more often. This can be weekly and it is work! In reality, the average composter turns their pile once every 4 to 5 weeks. This mixes in the fresh material with the older, adds air to the pile and allows you to add water. With this method, a pile started in the fall, added to and turned the following summer will be ready in late fall of that year or the next spring.

If you are not adding lots of new material, turn and water the pile 5-6 weeks after initial heating. Make sure to turn the outside of the old pile into the center of the new pile. The compost should be ready to use 3 to 4 months later. In Illinois, a pile started in May should be ready by September-October of the same year.

How much water should you add? The squeeze test is an easy way to gauge the moisture content of the pile. The organic material should feel damp to the touch, with just one or two drops of water expelled when squeezed tightly in the hand.

What to do in the winter months is a common question. As the temperatures lower, the pile cools down and eventually all activity ceases. Most people let the pile shut down and plan to reactivate it in the spring. During extremely cold weather, the task of getting to your compost pile may be the most difficult. If you want to keep the pile active in the winter, you will have to insulate it. Covering the pile will help retain heat and prevent water buildup. During the winter, kitchen scraps are generally the only items added.

Problems

Symptoms Problem Solutions
Compost has unpleasant odor. Not enough air due to overwatering. Not enough air due to compaction. If odor of ammonia, too much nitrogen. Add dry materials such as cornstalks, leaves, or wood chips to soak up excess water.

Turn the pile to aerate. Cover pile if rains continue. Turn the pile to aerate. Add carbon materials and turn the pile to aerate.
Pile not heating up. Pile is too small. Insufficient moisture. Not enough air. Lack of nitrogen. Compost may be finished. Make pile bigger. Add water
while turning. Add water by sticking a garden hose into the center in several locations. Poke holes into the pile and add water using a watering can. Turn the pile to aerate. Mix in nitrogen materials. Add 10-10-10. Use it and start over!!!!
Compost is damp and warm only in the center. Pile is too small. Add more material.
Pile temperature exceeds 160°F. Not enough air. Lack of carbon. Turn the pile to aerate. Mix in carbon materials.
Large, undecomposed items are still in the mix. Low surface area. Remove items. Chop or shred before adding.
Rodents. Presence of meat scraps. Only add items recommended for your pile and remove offensive material. Animal-proof bin.
Compost pile has flies, earwigs, slugs and/or other insects. I find white material throughout my pile. Good! Pile is composting correctly. Insects are a sign of a productive compost pile. The white cobweb material are actinomycete, part of the microbial community. If there is an abundance of flies, bury your food scraps as you turn the pile.