As part of the Master Composter training, we're visiting hot-pile spots in New York City where we can see real-world applications of compost. Today's destination was the Battery Park City Conservancy, the organization that oversees the sublime, superbly manicured outdoor spaces located at the southern tip of Manhattan. This greenspace is a botanical paradise—not merely because it exists—but because all 32 acres are maintained organically. The Conservancy eschews pesticides and synthetic fertilizers, nurturing the flora with soil management techniques that employ tricks and techniques of compost.

T. Fleisher, director of horticulture at the Conservancy, is to the world of composting what Charlie Trotter is to cooking—someone who's reached the mystic dimensions of the artform. One of the first things that Fleischer will teach you is that not all compost is created equal. Depending on what goes into the pile and how it's cured, it will have a different balance of bacteria and fungi. Fungal-leaning compost is better for shrubs and trees; the bacterial dominant variety is good for flowers and herbs. For those home ‘posters and gardeners who want to find out what's in their homemade humus, you can send the material off to a lab.

The Conservancy's large-scale composting operation has been running for 15 years now. The org gathers all the organic debris and cuttings from the park—tree trimmings, grass cuttings, etc.—and also collects castoffs from Battery Park City grocery stores and Starbucks (coffee grounds). BPCC composts using several methods including an outdoor windrow (a large open-air pile) and the Earth Tub, an industrial grade composting container. Fleisher has the experience to prove that composting, when managed well, doesn't produce any unpleasant aromas. "We're composting 20 yards from the Ritz-Carlton Hotel," he explained. "We never have complaints about the odor coming from our site—we have complaints about starting to work early."

BPCC spreads compost tea—water that has been infused with protozoans, bacteria, nematodes, fungi, et al—on its greeneries to keep its lawns and flora healthy. This brew, which you can make at home with your own compost, protects plants from diseases and pests while helping them absorb nutrients from the soil. It's prepared by placing a mesh bag filled with compost into a water container with a bubbler in it (an aquarium filter will do the trick); the water is aerated for a while so that the microorganisms can permeate the liquid and to dechlorinate the tap water.

Here's where these prep techniques culminate: Fleischer and his team will apply a high-bacterial-content compost tea to turf areas; the bacteria soak up the available nitrogen and then slowly release it—which means that the plants absorb it in good stead, instead of mainlining the junk as they would with a synthetic fertilizer. I probably sound like a composting geek now, but there is a profound elegance in Fleischer's use of entirely natural methods to keep the BPCC garden healthy without the processed foods and poisons of industrial-grade horticulturing.