Composting is the controlled decomposition of organic materials. It results in an earthy, dark, crumbly substance that is excellent for adding to houseplants or enriching garden or landscape soil. One of the great aspects of composting is that the key ingredients are often things that you’d be tempted to throw away. So, with just a little effort, you can contribute less to the trash stream (good for the environment) and make great compost (good for your garden or landscape)!
Factors Affecting Compost
The moisture levels within the compost pile are critical! A handful of the compost mixture should be as moist as a wrung out sponge.
- Foul odors? The mixture is probably too wet. Add dry material and turn more often.
- Not decomposing? The mixture is probably too dry. Add water when it is being turned over.
Composting is an anaerobic process, meaning that the microbes decomposing the material in the compost pile need oxygen.
- Foul odors? The mixture may be too wet and oxygen levels are too low. In order to ensure that enough oxygen is available for the microbes, the compost pile should be turned over regularly.
Aerobic decomposition smells “earthy” and pleasant. The more often a pile is turned, the faster it will compost!
The middle of the compost pile will rise up to 150⁰ F as microbes begin digesting the organic material and increase their metabolic rates.
The high internal temperatures kill the pathogens and weed seeds in the compost pile.
The longer a compost pile has been active, the slower it will be to get internally hot. When the temperature in an older, mature compost pile doesn’t rise it means that the compost is ready for use.
Key Ingredients for Composting
Food for your little micro friends consists of two classes of materials, simply referred to as “Greens” and “Browns.”
Green materials are high in nitrogen, while brown materials are high in carbon. The green materials provide protein for the micro bugs, while the brown materials provide energy.
It is hard to have too much of the brown category. Too much green is usually the problem.
A pile of kitchen garbage will never become useful compost; it simply becomes a smelly pile of garbage. A good mix of browns and greens also helps the pile maintain the right amount of moisture and air.
Ideal Mixture of Browns and Greens!
The best combination of browns and greens is about 4 parts of “browns” to one part “greens” by volume.
If you have more browns, you’ll still get compost - it’ll just take a little longer.
If you are on the side of too much green, you’ll likely have a smelly garbage heap.
Typical green materials are:
- Fresh (green) Grass clippings
- Fresh manure (horse, chicken, rabbit, cow)
- Kitchen scraps (fruit, vegetables, coffee grounds, tea bags)
- Green leaves
- Leftover fruits from the garden
Typical brown materials include:
- Brown, dry leaves
- Dried grass
- Cornstalks (shredded)
Tools You’ll Need
Pitch fork, or turning fork – The best hand tool for mixing and turning a working compost pile. The tines of the fork will penetrate layers of leaves and grass clippings, and make the mixing process much easier than using a shovel.
Shovel – The best tool for removing finished compost from a bin or heap, and for tossing compost onto the garden.
Compost Thermometer – not essential, but you might be interested in checking the temperature of the “core.” A properly established mix will heat up to 160 degrees F, whether you have a compost thermometer or not.
How to Compost!
Step 1 - Choosing the Location
To make compost, you’ll need to dedicate some outdoor space to the process. Ideally, the location of your compost production should be convenient to the garden, as well as close to the source of the raw materials (kitchen scraps, lawn clippings, etc.), without being an unappealing eyesore.
Step 2 - The Compost Container
There are two basic kinds of compost piles: open bins and enclosed containers. Whether you choose to use an open bin or a compost container, two bins or containers are always better than one. Because the composting process takes at least several weeks under the best conditions, you cannot add additional materials to the heap without “resetting the clock” to day one.
Step 3 - Activators
Microorganisms and Size
You have some dry leaves and you’ll be adding green materials (lawn clippings, kitchen waste, plant scraps). If you’re starting with leaves and other natural materials, you’ve got bacteria and fungi that are eager to help you make compost. And, if you want to give the mix a little boost, one excellent and free additive is simply a shovel full of good garden soil, which is full of microbes as well.
Critical Mass – When is Enough Enough?
For efficient hot composting, you need to have a critical mass to generate a heat core. Most experienced composters agree that you need a minimum of 1 cubic foot of raw materials, of course, more is better. As soon as decomposition begins, the volume of the pile will decrease. Refrain from adding raw materials to your batch of working compost, and simply start a new batch with new raw materials.
Step 4 - Turn, Turn, Turn
You’ll maximize your composting efforts if you frequently turn, or mix, the heap. Mixing your heap will help to keep the browns and greens in balance, will distribute moisture, and add essential air (oxygen) to the mixture. The core (the inside) of the compost heap is always hotter and is the center of activity. The outside is generally less active and much cooler. While the compost is working, or “cooking,” the best tool for turning is a pitch fork or garden fork.
Don't Put These in Your Compost Pile!
It’s difficult to make sure that every speck of the diseased material gets fully composted and you could easily spread the disease to other parts of your garden.
CHEMICALLY-TREATED WOOD PRODUCTS
Sawdust from chemically-treated wood products can be bad stuff to compost, like arsenic, chromium and copper.
SHREDDED NEWSPAPERS OR OFFICE PAPER
The paper very likely contains chemicals that are not good for your compost.
MEAT, BONES, AND FATTY FOOD WASTES
In addition to attracting pests, fatty food wastes can be very slow to break down, because the fat can exclude the air that composting microbes need to do their work.
Dog and cat feces may carry diseases that can infect humans. It is best NEVER to use them in compost piles.
Some weeds can resprout from their roots and/or stems in the compost pile. Just when you thought you had them all chopped up, you've actually helped them to multiply!
Using the Compost
Screened compost (compost that has been sifted to collect the smaller particles) can be applied as a lawn fertilizer throughout the season. It will provide a wonderful slow-release food as well as assist in lawn disease prevention.
Compost is the single best additive for good, even great, garden soil. It improves fertility, water retention for sandy soils, water drainage for clay soils, and improves your soil’s disease fighting characteristics.
(seed starting, potted plants)
Compost can be used to create a very good seed starting mix, or it can be added to potting soil to create a nutrient-rich mixture.
Putting 3 to 4 inches of compost around landscape plants can not only help retain soil moisture, but can cool the soil on hot days and help prevent soil loss from vulnerable areas.