In Maine, where 38 percent of what we throw away can be composted, University of Maine Cooperative Extension Professor Mark Hutchinson is helping people do a better job composting yard waste and chicken scraps. He thinks composting can be fun as well as important, and he knows what he’s talking about. In the last 15 years, he has composted “everything from chickens to whales.” Here are some of his pointers.
Every summer, I throw yard waste and kitchen scraps into a pile in a corner of the yard and hope for the best, but I’m not sure this is the most efficient method of composting. What’s the best way to get started?
You want to have somewhere around a pile that’s 4 feet by 4 feet by 4 feet. That creates a thermal mass to keep the heat in place. If your pile is too small, you’ll lose the heat — that’s one of those “aha” moments I often get when teaching about composting. We get piles to 160 to 165 degrees without much effort in a commercial setting. Homeowners typically get temperatures as high as 110 degrees.
Wow, that’s really hot. Is that heat a sign the pile is decomposing? If that’s the case, I think mine is just sitting there.
You’ve got to think of the compost pile as feeding an organism. You want to feed the microbes. They’re the decomposers in the compost. They’re the ones that are doing the majority of the work.
How long does it take them to get the job done?
A commercial operation can make finished compost in three to four months. A home composter can probably make compost in six to eight months, depending on how active they are with it. My compost is usually 18 months before it’s ready to go into my garden.
What do you want in the pile?
You can put anything from vegetable scraps to plants you might be weeding out or taking out, as long as they haven’t gone to seed. You can put in leaves. You can put in weeds. In a home composting situation, think about how much green nitrogen source you actually have, versus a brown or carbon source. In the fall you’re going to have a lot of carbon rather than a lot of nitrogen. Sources of carbon are dead leaves, wood shavings and horse bedding. Sources of nitrogen are food residuals coming out of the kitchen, any type of dairy or chicken manure. In the pile here at my house, if you cut up a melon, you put in the rind. Coffee grounds. Eggshells. Lobster bodies, if you eat lobster. Paper towels. Those things are all acceptable in a home compost pile.
What don’t you want in there?
Do not put diseased plants in the compost pile. The reality is it’s difficult for homeowners to get the temperature high enough to kill plant diseases.
Any other no-nos?
If you’re in town next to someone else’s house, you probably don’t want any meats and bones in the pile. Meat fats draw critters you don’t want, such as rats, cats and dogs.
Is the location of the compost pile important?
The rule of thumb is high and dry. Find the spot in your yard where water does not accumulate. The pile does not need to be covered from rain, snow or sun.