Indoor Methods

In 2006, we Americans composted almost 65% of our yard waste and over 50% of used paper and cardboard but only 2.6 % of our food waste. We are currently throwing away almost 32 million tons of food and kitchen scraps a year. Most of it goes to landfills where it produces damaging methane gas and a variety of other environmental problems.

Indoor composting systems that make it easy to compost food could keep millions of tons of garbage out of landfills. Kitchen systems make composting available to people living in apartments and crowded urban environments, they make it easy for people who don’t want to slog through snow or mud to a compost pile during the coldest months of the year, and they make composting available to people who may not be well or strong enough to deal with an outdoor compost pile.

The claim that one can compost indoors may still raise eyebrows or draw forth hoots of derision in some circles, but increasing numbers of people are doing it. Most practice vermicomposting (worm composting) becoming what Mary Appelhof, the queen of vermicomposting, called “worm workers.” This method involves feeding vegetable scraps to worms kept in a special bin which can sit on a small table. Their offal, or castings, are amongst the richest and most highly prized of soil amendments.

A much smaller number of people are familiar with Bokashi composting which, like vermicomposting can be done indoors but which requires little in the way of special equipment — an airtight bokashi bucket and some inoculating material, which can be either bought, made with a store-bought starter, or made entirely from scratch.

Very recently, a whole new technology has been developed: indoor hot composters. For traditional gardeners, this is almost a contradiction in terms: hot composting means a pile that’s too big to manage indoors. The new composters aren’t the size of a traditional pile (thank goodness) and can’t handle that quantity of material; like Bokashi and vermicomposting, they’re primarily designed to dispose of kitchen waste. Despite their small size (20″x20″x12″), they can process 120 pounds of waste a month, as much as most families of five produce.

Several companies are producing these, but where the Panasonic costs close to $900, the NatureMill ULTRA costs less than half that (about $400), and the METRO a hundred dollars less again. The ULTRA appears to differ primarily in being a sturdier version of the METRO, with a three-year rather than a one-year warranty. They do require power, but much less than others on the market, or than you might expect: about ten watts. The power drives a small fan which ensures that the compost stays aerobic, but the composting heat itself is used to run some of the functions.

NatureMill Composter