Composting food waste takes four ingredients: browns, greens, water and air.

About 65 Polk County residents learned how to put thse ingredients together at a forum Tuesday night called “From Garbage to Garden.” (See page 6 for a fact sheet on composting.)

The Polk County Recycling Advisory Board sponsored the community forum to teach residents about composting Tuesday night.

Composting is a mix of the art of the gardener, the science of horticulture and the discipline of waste engineering. Compost happens, said keynote speaker Brian Rosa, an organic recycling specialist with the North Carolina Department of Environment and Natural Resources (DENR), Division of Environmental Assistance and Outreach.

Many of the residents who attended said they currently have backyard compost systems. They had many questions about what can be put in the compost and about worm boxes, or vermi-composting.

Rosa presented facts about composting and details of what is needed for both composting and vermi-composting.

He said there are more than 8 billion residents in North Carolina who generate more than 1 million tons of food waste per year.

North Carolina diverts six percent of its food waste, which is more than twice the national average, Rosa said.

So were way ahead of the curve, but we have a long way to go, he said.

The states hierarchy for waste is first to reduce waste, then to feed hungry people, then compost and the last resort should be the landfill.

With backyard composting, Rosa said residents can divert, or avoid sending to the landfill,&bsp; 1/3 of a ton of organics per household per year.

He also pointed out what the three arrows mean in the recycling symbol. The first means collection, next is processing and last is purchasing.

Complete the cycle, said Rosa.

Rosa detailed what is needed to make compost, which includes about 2/3 brown materials, which are dried and carbon-rich. Brown materials can include, chopped or shredded branches, shredded paper, paper towels, straw, leaves and soil, which are needed to introduce microorganisms necessary for decomposition.

The other third needs to be green, which are fresh materials that are nitrogen-rich. Greens include food such as bread, grains, pasta, grass clippings, eggshells, vegetable and fruit scraps, coffee grounds, filters, tea bags, fresh hay and small amounts of wood ashes.

The compost also needs to contain some moisture and have air flow. Composting works when the materials achieve a temperature between 130 and 150 degrees. The compost must be turned and takes between one month and four months depending on the size. The minimum size of an effective compost tub is 3 ft. by 3 ft., according to Rosa.

Vermi-composting with worms was also described as a fairly simple process. Rosa said the best worms to use are red wiggler worms.

Polk County Recycling Board members indicated they may plan a workshop to learn more about composting in the future. Rosa said he could show Polk residents hands-on how to compost and could bring worms and tubs to use. He said his workshops are about three hours long.

For more information on composting, visit Rosas website at www.p2pays.org/compost.