Composting

Compost Recipe

Organic Materials

A good mixture of 75% high carbon (browns) material, and 25% high nitrogen (greens) material is what you will need to start the composting process.

Note: To get the process going, it is a good idea to add some composting starter, too.

Moisture

Materials in the composting bin should feel moist, but not too soggy. In percentages, it should be about 40-60% water. A simple way to check the moisture content of the compost, is to squeeze a handful. It should feel like a well-wrung sponge.

Note: You may need to tarp your compost pile to keep it from getting too wet during extended rainy periods, or water it, during dry spells.

Temperature

Heat is created as organic materials decompose. The most efficient temperature range for a compost bin is between 90-140° F. Given the high temperatures required for rapid composting, the process will inevitably slow down during the winter months, in the Chicago area. Although, don't be surprised to see your compost bin steaming in cold weather. Some microorganisms like cool temperatures and will continue the decomposition process, though at a slower pace.

Note: Be careful to place your compost bin away from buildings and wooden fences, as fast composting can get very hot.

Air

As organic matter decomposes it takes up all the surrounding, available oxygen using a process called aerobic decomposition. Aeration of a compost bin can occur naturally by wind, or when the heated air from the compost bin rises, creating a draft of fresh air to the bin. So, you can leave nature to take it's course, but you can speed the composting process a bit, if you take a pitchfork to your compost every week, and shuffle the contents around a bit, adding some fresh air to the process.

Note: If your compost bin starts to smell, that's anaerobic decomposition, and a little aeration will go a long way in "freshening up" the old compost pile.

Organic Materials

High Carbon (brown - 75%)

• leaves
• dead plants
• straw
• shredded paper
• shredded twigs
• pine needles
• sawdust (untreated lumber)

High Nitrogen (green - 25%)

• grass
• green weeds
• manure
• alfalfa
• clover
• seaweed
• pond algae
• non-meat & non-dairy kitchen scraps
• egg shells
• coffee grounds
• tea leaves

Composting Starter

• old compost
  (borrow a bucket from the neighbor)
• soil
• cow manure
• chicken manure
• horse manure
• commercially available compost "starters"

DON'T COMPOST!

Below is a list of items to keep out of the compost pile, as they can have a negative effect on the composting process, and cause you much grief in the garden.

• diseased plants
• leaves from diseased trees
• persistent weeds
• poison ivy or poison oak
• human or pet feces
• meat or dairy products
• vegetables cooked in animal fats
• plants that have gone to seed
• chemicals

The Compost Bin & Other Supplies

An area approximately 4'x4'x4', out of direct sunlight is ideal for your compost pile. Choose an easily accessible spot on the ground, not concrete. Compost piles don't need to be enclosed, although most people use a bin or similar enclosure. Compost bins can be purchased, or you can easily construct one with common materials such as chicken wire, snow fencing, lumber or used pallets. Other tools that come in handy for composting are a garden hose for watering the pile, wheelbarrow for delivering organic material & collecting compost to use in the garden, and a shovel & pitchfork.

Note: Composting can begin any time of the year, but starting in the fall when leaves are abundant make it easier to collect up the 75% brown material.

Using Compost

Compost is ready to be used when it looks dark and crumbly and none of the starting ingredients are visible in their previous form. One way to test if your compost is finished, is to seal a small sample in a plastic bag for 24 to 48 hours. If no strong odors are released when you open the bag, the compost is done.

Compost can be applied directly around the base of trees and shrubs to serve as a mulch. Or, it can be worked into the top six to eight inches of the soil to provide increased water retention and valuable nutrients to your garden soil.

Worms & Dirt (vermicomposting)

Vermicomposting or worm composting is the easiest way to recycle certain food wastes, and is ideal for people who do not have an outdoor compost pile.

Composting with worms utilizes vegetative food wastes (recycling rather than creating trash) creating a worthwhile garden product of high quality "worm casting" compost.

It is done with "redworms" (Eisenia foetida) who are happiest at temperatures between 50-70° F. They can be kept indoors at home, school, or the office. As with outdoor composting, keep the food waste scraps to vegetables & peelings, egg shells, coffee grounds, and tea leaves.

Place redworms are placed in a plastic box or bin (with air vent holes) which can be built or purchased, along with "bedding" of shredded cardboard and/or paper moistened to about 75% water content. The container should be wide enough so that food scraps can be buried in a different location each time. The dimensions of the container and the amount of worms required initially will depend on how much organic food waste will need to be composted each week, but an average family can get away with a box about the size of a shoebox.

Visit our worm composting page to build your own bin for under $20!

For more information on composting, consider viewing The University of Illinois Extension - Chicago Home Composting site:

urbanext.illinois.edu/homecomposting/

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