Howto:Compost outdoors

Courtesy of the Lower East Side Ecology Center

What is composting? Composting is the process of creating the ideal conditions for the rapid decomposition of organic materials. You can think of composting as speeding up the way nature recycles. In nature, when a leaf falls to the forest floor, it is consumed and digested by a host of creatures, from worms and insects to microorganisms such as bacteria and fungi. When we make a compost pile out of our organic materials, we are creating the conditions (heat and moisture) that these decomposer organisms need to thrive. Only organic materials can be composted—and to prevent disease and odors, certain materials, such as animal products, shouldn’t be.

When the decomposer organisms have done their job, what starts out as fruit and vegetable scraps—which would have wound up in your garbage can—becomes a nutrient-rich material called compost, a dark, crumbly material that looks and feels like potting soil. Adding compost to soil is an excellent way to improve soil texture: it loosens heavy clay soils, making them better for root growth, and it helps light, sandy soils retain water and nutrients. Compost suppresses diseases, provides vital aeration to plant roots, and is a source of minerals and nutrients that are essential to plant growth and health.

What you’ll need:

 * A compost bin – which you can purchase or make yourself by using a wooden crate or chicken wire
 * Organic material to start your composting base – dry leaves are preferable but you can also use some finished compost, used or new potting soil, or shredded newspaper.’
 * Water
 * Food scraps
 * Re-sealable container or a large zip-lock bag
 * Long-handled rake, shovel, or a long stick

1. Set up your bin:
Compost bins are really just containers for your compost pile that serve to keep warmth and moisture in, and keep pets, rodents, and other pests out. They also help keep your pile sightly, tidy, and compact, which can be especially important in small yards. People set up compost bins on terraces, roof gardens, patios, next to outdoor garbage cans, in courtyards, side alleys, and community gardens. Choose a compost bin based on the space you have available for composting, the materials you want to compost, your budget, and the amount of time you want to spend tending your pile. Call the compost helpline in your borough to find out about compost demonstration sites or to obtain more information about buying or building a compost bin.
 * Holding units are the simplest type of bin. These bins are most appropriate for composting fall leaves and yard trimmings. You can construct your own using inexpensive or recycled wood, or chicken wire. Simply add materials and leave them to decompose. This method requires little work, but can take from six months to a year to make finished compost. If you want to continue to add materials, you will most likely need more than one holding unit—which can take up room in a small yard. If you are planning on adding kitchen scraps, you should consider using an enclosed bin, which provides more effective protection against pests.
 * Enclosed bins are suited to handle both yard trimmings and kitchen scraps. They are most appropriate for small yards or any small space, such as a side alley, roof garden, or terrace. If you live in a multiunit building and are placing your compost bin near outdoor garbage and recycling cans, make sure you visibly label your bin so that other residents do not accidently place refuse or recyclables in it. You can construct an enclosed bin by drilling ventilation and drainage holes in the lid, sides, and bottom of a 20- or 30-gallon garbage can or barrel. Ventiliation helps the material become compost more quickly. The Botanical Gardens also sell commercially available compost bins at a discounted rate, through a subsidy provided by the Department of Sanitation.
 * Rodent-proofing should not be necessary if your compost bin is enclosed. However, if rats or other pests are a problem in your area, you can take additional steps to rodent-proof your bin:
 * Add screens to areas where rats and other burrowing animals can get through.
 * If your bin is placed on the soil, lay a piece of screen between the soil and the bottom of the bin.
 * Be sure to keep your pile moist and turn material regularly to increase the temperature in order to prevent nesting by rodents.
 * In especially tough cases, you can add a screening barrier vertically 6 to 8 inches into the ground around the perimeter of the bin.

2. Add organic materials:
Fill the entire bin with fall leaves or other dry organic materials from your yard. Make sure to cut up or shred any large pieces. A good time to begin composting is in the fall, because fall leaves are an easy material with which to start your bin. You should also stockpile leaves in bags to have on hand throughout the year to cover kitchen scraps or balance out “green” yard trimmings. If you don’t have any fall leaves available, or want to begin composting during another season, you can start your bin with some finished compost, used or new potting soil, or shredded newspaper or brown paper. Fill the bin about one third full.

3. Add water:
If you are starting your bin with fall leaves, dry yard trimmings, or shredded newspaper, it is important that you add water. Add at least 3 gallons of water to a 30-gallon homemade garbage can composter, or 5 gallons to a commercial compost bin. Be sure to mix the leaves as you sprinkle the water so as to evenly coat and soak them. The leaves should glisten with moisture. Shredded paper should be wet, but not “mushy.” Continue to add water, especially during periods of little or no rain. If you’re starting your bin with finished compost or potting soil, you don’t need to add water at the beginning. However, it is essential to monitor moisture levels and add water so that your compost pile remains moist and never dries out.

4. Add food scraps:
Once you have started your bin with fall leaves, finished compost, shredded newspaper, or potting soil, you are ready to add food scraps. A convenient way to store kitchen scraps is to put them in a re-sealable container or a large zip-lock bag and place them in the refrigerator or freezer. The main thing to remember when adding food scraps is that it is important to bury them under a thin layer of finished compost, shredded newspaper, or fall leaves. This will disguise the scent of the food and deter pests and flies. Again, if you have the space for extra bagged fall leaves, keep a supply throughout the year to cover food scraps. Remember, in general you want to add twice as much material from the “brown” (high carbon) list as the “green” (high nitrogen) list below.


 * What to compost:
 * Browns(Materials rich in carbon)
 * Fall leaves
 * Dead plants
 * Straw and hay
 * Pine needles
 * Small twigs and wood chips
 * Sawdust and woodshavings
 * Shredded newspaper
 * Egg shells
 * Corncobs
 * Bread and grains
 * Wood ashes
 * Old potting soil
 * Food-soiled paper towels and napkins
 * Dried flowers
 * Organic materials used for packaging (shredded paper and cornstarch packing peanuts)
 * Food-soiled cardboard (recycle if clean, but compost if dirty)
 * Stale flour, cereal, spices, beans
 * Nutshells
 * Greens(Materials rich in nitrogen)
 * Fruit and vegetable scraps
 * Coffee grounds and filters
 * Tea bags
 * Fresh leaves
 * Green plants
 * Prunings and hedge trimmings(chop or shred larger pieces)
 * Grass clippings
 * Weeds
 * Flower bouquets
 * Seaweed
 * Feathers
 * Horse manure
 * Manure and bedding from hamsters, gerbils, rabbits, etc.
 * Brewery waste (hops and pomace)
 * Spoiled juice
 * …and what to avoid:
 * Meat and fish scraps
 * Invasive weeds
 * Cheese and dairy products
 * Weeds with seeds
 * Fats, oils, and grease
 * Pesticide-treated plants and grass clippings
 * Dog and cat feces, kitty litter (handling these might expose you to disease pathogens)
 * Diseased plants
 * Sand
 * Dead animals
 * Coal and charcoal ashes
 * Large branches (chop them up first)
 * Colored or glossy paper
 * Pressure-treated plywood such as plastics, metals, and glass and lumber
 * Non-compostable materials such as plastics, metals, and glass

5. Mix the compost pile:
In order for the microorganisms in your pile to do their work, they need water, a good mix of materials, and air. The steps above address the first two components, so let’s look at how you can get air into your compost pile. Initially, make sure to mix the pile ingredients. Then as part of maintaining the pile, from time to time mix or turn your compost. This means taking a long-handled rake, shovel, or even a long stick and pushing it down into different parts of the pile and “fluffing” the pile up. Try moving the inside of the pile outward toward the edges and the outer areas to the inside of the pile. For the best results, turn your pile about once a month. In composting, like cooking, you learn as you go along. Find a turning schedule that works best for you.

6. Wait!:
Continue to add and mix organic materials…check on the bin to make sure there is adequate moisture and turn the pile.

7. Use your compost:
Finished compost resembles dark, crumbly topsoil and should bear no resemblance to the original materials. Compost should have a pleasant, earthy smell to it. A quick test to see if your compost is finished: Place some of the compost in a sealed plastic bag. Wait a few days. If you open the bag and it does not smell, your compost is done. If it smells rotten, put it back—it’s not finished.

Conclusion/Next Steps
Congratulations! You have just created your very own nutrient-rich compost. If you have ever bought and used peat moss, wood chips, manure, or topsoil, then you already know how to use compost. Mix compost into flower and vegetable beds; blend it with potting soil to revitalize indoor plants; or spread it on your lawn as a fertilizer. Use coarser compost as a mulch around trees and shrubs. If you prefer finer compost, you can screen it to sift out the bigger pieces. Do not place compost as mulch directly against tree trunks, as this will damage the tree. Using “unfinished,” or immature, compost in the garden can steal nitrogen from garden soils, so make sure to set this material aside until it is fully cured. You can store it in an open container next to your compost bin. In the fall, you can incorporate unfinished compost directly into flower or vegetable beds; the material will mature over the winter and be ready for spring plantings.