THIS article is the first in a series on backyard composting, and is based on a presentation by Ms. Rhonda Shermon, an Extension Specialist in the Department of Biological and Agricultural Engineering at North Carolina State University, USA. Ms. Shermon was recently in Guyana in her professional capacity at the invitation of the Partners of Americas Farmer-to-Farmer programme.

So, what is composting?

Composting is a controlled decomposition process that converts organic materials, such as leaves, kitchen scraps and garden waste, into a valuable product, called compost, or manure, as it is better known locally.

When compost is mixed with soil in gardens, lawns and house plants, it improves soil quality and results in healthier plants.
In short, it improves poor soils.

People have been composting for centuries, and references to composting were recorded on clay tablets in Mesopotamia in 500 BC.

As both an art and a science, composting is more like making soup than making a cake. There is no reason to put food waste and yard waste in the trash, when it can easily be composted in your back yard.

What compost looks like: Compost is dark brown or black in colour; has a crumbly texture; is humus-rich; and smells like soil.

Plants that benefit from compost:  Seedlings, potted plants, garden and field crops, lawns and trees may all benefit from compost.

What can be composted: Organic materials such as food scraps, food preparation residuals, food-soiled paper products, grass clippings, aquatic weeds, brush and tree trimmings comprise over 60% of our waste stream, and can be recycled by composting.

Organics such as spoilt fruits or vegetables can be stored in a container until you are ready to add them to your compost pile.
Some people place organics in a bag or container in their freezer until they can take it out to a compost pile. Others reuse a plastic container with a lid, or use a purchased compost kitchen container and keep it under their sink or on the kitchen counter.

The following organic materials can be added to your compost bin or make manure: Leaves, grass clippings, sawdust from deciduous hardwood trees; aquatic weeds, vegetables and fruits, coffee grounds and filters, tea bags and tea leaves; twigs, egg shells and crustacean shells, paper rolls, toilet paper, newspapers,  office paper, junk mail,  envelopes, paper napkins and bags, cereal and pizza boxes; literally all paper products; nut shells, vacuum contents and floor sweepings; hay; straw;  manure from rabbits, cows, horses, sheep or chickens; dregs from juice, beer and wine, and  male (not female) urine.

What not to compost: There are several types of organic materials that should not go into compost piles. These including the following: dog or cat faeces; and litter and dirty diapers (these may contain parasites and pathogens); meat, fish, bones; fats, grease, lard, oils; eggs or dairy products such as butter, milk, yogurt and sour cream (these create odours and attract rodents and flies); yard trimmings treated with chemical pesticides (these may kill beneficial composting organisms); diseased or insect-infested plants (the disease may survive and be transferred to other plants); weeds that have gone to seed; weeds with invasive roots, such as duck weed, alligator weed, or Bermuda grass; used facial or toilet tissue (they may contain pathogens); charcoal ash or coal (may contain substances harmful to plants); lime (can cause release of smelly ammonia gas and leave the compost with less nitrogen); pressure-treated lumber, pressed wood and plywood (these contain toxins); and heavily coated paper (magazines, catalogues, wrapping paper, greeting cards with metallic links, or photographs).

NEXT WEEK: What do I do first in composting?