The Carbon/Nitrogen Ratio

Scraps to compost fall into two basic categories: carbon-rich “browns” and nitrogen-rich “greens.” You need more carbon in your mix than you need nitrogen, with an optimum carbon/nitrogen ratio of about 3:1.

If there is too much carbon (browns), decomposition will slow down. If there is too much nitrogen (greens), your pile may end up a little pungent.

Generally, meeting this ratio means adding about one part brown for every two parts green, giving the decomposers a balanced diet with enough energy and nutrients to eat through everything you compost.

Carbon-rich “browns” tend to be dry, woody materials. Nitrogen-rich “greens” are usually colorful (think fruits and veggies) and usually a little moist. Here are a few examples:

Browns (Carbon-rich)

• Dried leaves
• Sawdust and woodchips (make sure these are from untreated wood)
• Shredded black and white newspaper
• Egg cartons
• Cardboard
• Dead, dried-out plants (disease-free)
• Tree bark
• Straw
• Peanut shells

Greens (Nitrogen-rich)

• Fruit and vegetable kitchen scraps
• Coffee grounds and tea bags
• Green garden cuttings
• Fresh leaves and flowers
• Grass clippings

Turning Your Compost

Periodically turn your compost with a pitchfork or shovel so the new material ends up on the warm interior of your compost pile.

Turning your pile also infuses your pile with oxygen (also known as “aeration”), which is essential for the aerobic bacteria that help decompose the material.

If you have not added materials to your compost heap in a while, make sure you still turn the compost every so often. If the material gets too dry, you can water it with a hose (moisture content should be about 50 percent) to maintain the moisture that the composting microbes need.

Other Tips for Healthy Compost

Compost Odor

Smells are a bad sign for your compost. If you avoid adding meat and oily foods to your pile, which can attract pests, your compost should not give off odors.

Strong, foul smells usually indicate that the aerobic bacteria in your compost are struggling for one reason or another. Remedy the smell with these quick pointers:

• Turn your compost: You may have a heap full of stinky anaerobic bacteria if you are not turning your pile frequently. Try turning your pile every few days to infuse the pile with oxygen so that odor-free aerobic bacteria thrive and anaerobic bacteria do not.
• Add more browns: If your pile smells like ammonia, you’ve added too much green. Try adding more browns for each part green to for a balanced carbon/nitrogen ratio.
• Top with dirt: You can prevent smells by adding an extra layer of dirt or other brown covering over the top after turning and mixing in more browns.
• Avoid meat or oils: If you don’t mind attracting wildlife to your yard, you can feel free to include meats and oils in your compost. It’s wise to avoid these items, however, if your compost is close to your home or if you live in an urban or suburban area.

Good Scraps for Composting

Food scraps

• Fruit and vegetable peels and scrap
• Plate scrapings (excluding meat, bones, dairy products, oily and greasy foods – see below)
• Egg shells
• Tea bags (remove the staple!)
• Coffee grounds and filters
• Grains (breads, cereals, rice, pastas, etc.)
• Nut Shells
• Fruit pits
• Bottle corks

Yard trimmings

• Leaves, straw, pine needles
• Fresh or dried grass (as with all items on this list – chemical-free only)
• Flower and plant clippings
• Weeds that have not gone to seed
• Houseplants and potting soil
• Wood ash

Paper products

• Paper items (napkins, paper towels, shredded brown bags, etc.)
• Shredded cardboard boxes
• Shredded black and white newspaper
• Non-glossy junk mail
• Bedding from hamster/gerbil/rabbit cages
• Paper coffee filters

Source: FoodPrint