All Princeton area homeowners have two things in common — terrible soil and lots of kitchen waste. Combine the two, and the result can be greener lawns, more gorgeous flowers, healthier trees, and fewer bags of soggy garbage to haul to the curb.

Turn all of those melon rinds and tea bags into compost, urges Barbara Bromley, director of the Rutgers Cooperative Extension in Mercer County. “It’s one of only a few things a homeowner can do to help the environment.”

It’s a natural process, it’s easy to do, and it does wonders for the typically hard, clay-based soil in our area, soil that makes for anything but ideal growing conditions.

“Nature has been composting for years,” Bromley points out. “You don’t need to put fertilizer in the woods.” Whether it’s a stand of trees behind a suburban development or a 100-acre wood far from civilization, woods are self-renewing. Branches, pine cones, and leaves — and Bromley points out, little dead bunnies — fall to the ground and decay, creating an ideal environment for seeds, which propagate and grow like crazy — all without one whit of human intervention.

The same beneficial effects of compost can work wonders in suburban lawns and gardens. To date, an obstacle to taking advantage of composting has been an obsession with order. “We’ve become nutsy neat,” says Bromley. An example is the totally unnecessary collection of grass clippings. “They should be left,” she declares. Soon enough, they will decompose, thereby enriching the soil and saving landfills from dealing with still more organic materials.

Leaving grass clippings where they fall is more than easy, and many a youngster charged with raking them up would rejoice to hear that the chore is unnecessary.

Creating a compost heap is not much more difficult. Bromley herself, who studied plant science at Rutgers (Class of 1970), and has been working with the cooperative extension since 1978, has been composting at her Hamilton home for 28 years.

She uses a stainless steel bucket with a lid to collect kitchen waste, but says that any kind of container is fine, “anything with a lid.”

So what goes into the container? “Tea bags, tags and all,” says Bromley. “Coffee grounds — with the filters, celery stalks, potato peels, rotten berries, that green thing in the back of your refrigerator.” Most of what would go down a garbage disposal can go into the collection pail.

But that’s not all. “Some people add leather,” says Bromley.

She is most delighted when scraggly, 90 percent dead house plants make it to the compost pile. She senses that many people have trouble letting go of the geraniums and African violets that they have nurtured. Knowing that the over-the-hill plants will give birth to new life could be the incentive they need to let go.

Most people are less sentimental about paper, and have lots of it around the house. Speaking of perhaps the most despised class of paper, she says “You can shred your bills and mix them in with coffee grounds.” Newspapers are fine too, and there is no need to worry if some of its pages contain color. These illustrations used to be made with chemicals, but are now more likely to be made with vegetable dyes.

Be a little careful with paper towels,” Bromley cautions. They can certainly be added if they were used to wipe up milk, but if they contain cleaning fluids they should not go into the compost pail. This is so because bleach will kill off some of the microbes that need to do the work of breaking down the waste and creating compost.

Also be careful with plate scrapings. All of the vegetables can go into the pail, but the meat should stay out. “It will compost,” says Bromley, “but it will attract animals you don’t want — and it will stink.” Keep piles of leaves out of the mix too. When wet they tend to clump together and will blot out the oxygen. But it is all right to add leaves if they have first been ground up with a lawn mower. One more item to keep out is used kitty litter. “Don’t put in feces from animals that eat meat,” says Bromley. Those from rabbits, and similar vegetarian pets, are fine.

Bromley is anything but authoritarian. If a stray Windex-coated paper towel gets into the mix, it’s not the end of the world. She also says that it’s a good idea to chop up waste — melon rinds, for example — because smaller pieces will compost more quickly. But she acknowledges that “there’s no need to run everything through a food processor.”

A compost pile can be simply that, a pile. Or it can be a box — homemade or store bought. Bromley says that there are many composters on display at the county demonstration site on Federal City Road in Pennington, where a composting demonstration takes place on Sunday, April 30, at noon.

The ideal size for a composting box ranges from between 3’ x 3’ x 3’ and 6’x 6’ x 6.’ A box this size, filled with composting materials, will heat up to about 140 degrees. It can be covered, says Bromley, and it’s a good idea to place it in the shade. Composting does not require light, she points out, just water and oxygen. A compost pile sitting in the sun can dry out, robbing the process of needed moisture.

The compost pile needs to be turned — perhaps with a pitchfork or a turning fork — about once a week. This ensures that oxygen will continue to permeate the mix.

“A compost pile should be as damp as a wrung out sponge,” says Bromley. It can’t be dry, but it shouldn’t be too wet. The most important way to attain this texture — and to ensure that composting does indeed occur — is to add “browns” to the mixture.

“You need equal weights of browns and greens,” says Bromley. “Not equal amounts, equal weights.” The greens — all of that kitchen waste, plus weeds, fresh leaves, scraggly plants, and manure — provide nitrogen. The browns are things like sawdust (from untreated wood only), wood chips, dry leaves, cardboard, and shredded paper. They provide carbon. Another help in figuring out what is nitrogen and what is carbon is that the nitrogen-rich greens are also referred to as “wets,” and the carbon-rich browns and are also referred to as “dries.” To judge the relative weights of the browns and greens is to keep in mind that seven bags of browns equals one bag of greens — approximately.

Again, don’t obsess. Just try to keep close to the seven-to-one ratio. The moisture of the compost pile will provide guidance. If it’s too wet, add more browns. If it looks dried out, throw in some more greens.

It takes about four to six weeks to create compost during the growing season, says Bromley. The process can be speeded up by shredding or chopping everything that goes in to the compost pile or by using an upscale composting tumbler that comes with a hand crank and instructions to turn the mixture frequently. One such device is made by a company called ComposTumbler ( It promises to turn yard waste into compost in two weeks in what it calls “a 14-day miracle in your yard.” Tumblers cost anywhere from about $150 to $300. In addition to faster composting, these enclosed composters ensure that odors are not an issue. There is a good selection online at the Gardeners Supply Company (

Whether or not miracles are involved, Bromley says that you’ll know you have compost when the pile “looks like nothing that you put into it.”

She spreads her compost everywhere — on her lawn, around her trees, and in her garden. It’s a good idea to keep invasive weeds, or weeds with lots of seeds, out of the mix, but still, the compost may cause a few weeds to sprout. Not a problem. Says Bromley, “What compost does for the soil so outweighs weeds.”

– Kathleen McGinn Spring

Composting Demonstration, 431A Federal City Road in Pennington (, Sunday, April 30, noon. 609-989-6830.

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