Posted on | March 4, 2009 | 3 Comments
Finished compost, sometimes called humus (not to be confused with the middle eastern delicacy made out of chick peas), is dark brown or black and looks and smells like good, healthy, fertile dirt. Compost is the result of the managed decomposition of yard trimmings, kitchen scraps and leaves.
You can drastically reduce your waste stream by composting kitchen scraps, shredded newspapers and a very long list of other things! You are basically using your trash to create dirt. It’s a beautiful thing. Compost can reduce the need for fertilizers and pesticides. By diverting so much stuff from the landfill you are also helping to prevent contamination of our waterways.
OK, I’m sold, how do I make compost?
Organic wastes are combined in proper ratios (more about this later) into a big pile or bin in the backyard; bulking agents (e.g., wood chips, shredded newspapers) and water are added as necessary to accelerate the decomposition and the pile is aerated (achieved by mixing or turning the pile) to finish the process.
Creating compost is different from natural composting (when leaves and vegetation fall to the ground, slowly decay and provide minerals and nutrients needed in soils) because artificial composting generates high temperatures which destroy pathogens and weed seeds that natural decomposition does not destroy.
Depending on your available space, you can compost outside or in your kitchen.
The most common type of composting takes place in backyard piles, heaps or bins. If you live in the 5 Boroughs, you can purchase a compost bin at cost from NYC’s composting project. We got our Garden Gourmet (shown at right) from this project a few years ago.
Most composting requires three basic ingredients:
- Brown stuff — Includes materials such as dead leaves, branches , twigs. Browns provide carbon for your compost.
- Green stuff — Includes materials such as grass clippings, vegetable waste, fruit scraps, and coffee grounds. Greens provide nitrogen.
- Water provides moisture to help breakdown the organic matter.
Some tips from experience (ok, my husband does most of the composting but I watch and learn):
- For the best compost, make sure you use approximately equal amounts of browns and greens in alternating layers before adding water or you will have a very slimy pile indeed.
- If you chop up the materials into small pieces, they will compost faster.
- Native materials will compost faster than non-native materials. For example, orange peels and pineapple cores don’t compost very quickly here in NYC.
- An entire winter’s of kitchen scraps translates into a surprisingly small amount of compost.
- If you are using piles, make 2 separate piles, one for new scraps and one for old so the compost has time to mature.
- Keep the pile far enough away from where you live to avoid smells and possible rodents but close enough to conveniently bring out the kitchen scraps on a daily basis.
Click on this link to see a great slideshow called “composting for kids”. It could also be called “composting for New Yorkers” because it shows you how to start a compost pile with no previous experience. If you want to print it out and take it outside with you you can download a pdf here.
If you do not have space for an outdoor compost pile, you can compostindoors using a special type of bin, which you can buy or make yourself.
The least expensive method: Build Your Own Indoor Bin
- Drill 1/2-inch diameter holes in the bottom and sides of a plastic garbage can.
- Place a brick in the bottom of a larger garbage can, surround the brick with a layer of wood chips or soil, and place the smaller can inside on top of the brick.
- Wrap insulation around the outer can to keep the compost warm and cover the cans with a lid.
If you want a composting appliance – this one uses electricity (but at least there are no worms involved.) Check out Reaction’s review of the Nature Mill undercabinet composter.
Another method of kitchen composting involves Bokashi, a wheat bran which has been inocculated with molasses, water and Efficient Microbes–a blend of yeasts and bacteria which are helpful rather than harmful. This miracle substance allows you to compost quickly (2 weeks) without using layers of brown stuff and you can compost meat, fish and other substances that you would normally keep out of the compost pile.
and now we come to the worms.
Another popular(?) method of undercabinet composting is called vermicomposting, in which worms are enlisted to speed up the decomposition of organic material, eating through scraps of it and excreting the “castings” that make up compost. You can read a recent NYT article for more information.
To review – What to compost:
- Cardboard rolls
- Clean paper
- Coffee grounds and filters
- Cotton rags
- Dryer and vacuum cleaner lint
- Fireplace ashes
- Fruits and vegetables
- Grass clippings
- Hair and fur
- Hay and straw
- Nut shells
- Shredded newspaper
- Tea bags
- Wood chips
- Wool rags
- Yard trimmings
What to leave out and why:
- Black walnut tree leaves or twigs: Releases substances that might be harmful to plants
- Coal or charcoal ash: Might contain substances harmful to plants
- Dairy products (e.g., butter, egg yolks, milk, sour cream, yogurt): Create odor problems and attract pests such as rodents and flies
- Diseased or insect-ridden plants: Diseases or insects might survive and be transferred back to other plants
- Fats, grease, lard, or oils: Create odor problems and attract pests such as rodents and flies
- Meat or fish bones and scraps: Create odor problems and attract pests such as rodents and flies
- Pet wastes (e.g., dog or cat feces, soiled cat litter): Might contain parasites, bacteria, germs, pathogens, and viruses harmful to humans
- Yard trimmings treated with chemical pesticides: Might kill beneficial composting organisms
Uses of compost:
You can use compost as mulch, fertilizer, soil enhancer. However, let me warn you against using compost for indoor plants or you might end up with a monster houseplant. Click here to see what went awry when we tried to improve our indoor air quality with houseplants planted in compost.
Let us know how it goes!