What to Compost - The IN List

• Animal manure

  Horse, Cow, Goat, Rabbit, Chicken - Whatever eats grasses and seeds and other organics. Not from animals that eat meat.

• Cardboard rolls

• Charcoal - Not the Commercial Processed Kind

  I make my own. I get hardwood logs and make it my self. I put all my logs in a pile, get a good fire going really hot, then cut off it's oxygem. That's pretty much a simplified version. For more complete instructions look here: How to make Charcoal #1 Or here: How to make Charcoal #2 I actually made it using my compost pile to cut off the oxygen to the fire. It cooked for 2 days under the pile and I had to wet it down several times and seal up places where it burned through to the outside. But, it worked very well.

• Clean paper

• Cotton Rags

• Dryer and vacuum cleaner lint

• Fireplace ashes

  Ashes will change the PH of your pile Wood ash does have fertilizer value, the amount varying somewhat with the species of wood being used. Generally, wood ash contains less than 10 percent potash, 1 percent phosphate and trace amounts of micro-nutrients such as iron, manganese, boron, copper and zinc. Trace amounts of heavy metals such as lead, cadmium, nickel and chromium also may be present. Wood ash does not contain nitrogen. The largest component of wood ash (about 25 percent) is calcium carbonate, a common liming material that increases soil alkalinity. Wood ash has a very fine particle size, so it reacts rapidly and completely in the soil. Although small amounts of nutrients are applied with wood ash, the main effect is that of a liming agent. Increasing the alkalinity of the soil does affect plant nutrition. Nutrients are most readily available to plants when the soil is slightly acidic. As soil alkalinity increases and the pH rises above 7.0, nutrients such as phosphorus, iron, boron, manganese, copper, zinc and potassium become chemically tied to the soil and less available for plant use. Applying small amounts of wood ash to most soils will not adversely affect your garden crops, and the ash does help replenish some nutrients. But because wood ash increases soil pH, adding large amounts can do more harm than good. Keep in mind that wood ash that has been exposed to the weather, particularly rainfall, has lost a lot of its potency, including nutrients.

• Grass/Lawn Clippings

  Actually, it's usually easier to leave grass clippings in the lawn, where they will decompose and benefit the soil directly. However, they can be composted, too. Be cautious to add grass clippings in very thin layers, or thoroughly mix them in with other compost ingredients, as they otherwise tend to become slimy and matted down, excluding air from the pile. Fresh grass clippings are high in nitrogen, making them a 'green' compost ingredient.

• Hair and Fur

• Hay

  Farmers are often very happy to get rid of spoiled hay bales that have been out in the rain, and will give them away or sell them at a low price. Grass hay will probably contain a lot of seed, which can resprout in your garden. Alfalfa hay will compost very readily. The greener the hay, the more nitrogen it contains. Be sure that any hay you plan to compost is well-moistened prior to addition to the pile.

• Houseplants - Dead ones usually and the Potting Soil they were in

• Kitchen Wastes

  Fruit and vegetable peels/rinds, tea bags, coffee grounds and filters, eggshells, and similar materials are great stuff to compost. They tend to be high in nitrogen (this puts them in the 'greens' category), and are usually quite soft and moist. As such, kitchen wastes need to be mixed in with drier/bulkier materials to allow complete air penetration. Many people compost their kitchen wastes in enclosed worm bins or bury them 8" deep in the soil, to keep from attracting pests to an outdoor compost pile (check with your local government to see if it has regulations about this -- some forbid open piles containing food wastes because of the pest issue). Avoid composting meat scraps, fatty food wastes, milk products, and bones -- these materials are very attractive to pests.

• Leaves

  If you live in an area where autumn leaves are still thrown away as garbage, cash in on the bounty each year by acquiring your neighbors' leaves! Generally, leaves are an excellent compost ingredient. They can mat down and exclude air, though, so be sure that any clumps are thoroughly broken up, or that the leaves are only used in very thin layers. Ash and poplar/cottonwood leaves can raise soil pH if used in compost -- this may not be beneficial if your soil is already alkaline, as many soils are in the West (especially in semiarid and arid climates). Dead, dry leaves are in the 'browns' category, while living green leaves contain abundant nitrogen and are considered 'greens'.

• Nut shells

• Pearlite and/or Vermiculite

  Both Pearlite and Vermiculite will add soil conditioners to your pile and later your garden. Additionally, will help to break up or avoid matting and clumping of greens. Furthur they will help aerate your pile

• Shredded newspaper

• Straw

  Dry straw is a good material for helping to keep a compost pile aerated, because it tends to create lots of passageways for air to get into the pile. Be sure to wet the straw, as it is very slow to decompose otherwise. Straw is definitely a 'brown' and also requires mixture with 'greens' to break down quickly. Many stables use straw as a bedding material for horses -- straw that has undergone this treatment is mixed in with horse manure and breaks down more quickly.

• Wood Chips and Sawdust

  Wood products belong in the 'browns' category, because they are fairly low in nitrogen. Some sawdusts, especially from broadleaved/deciduous tress, will break down quickly in an active compost pile. Others, especially from coniferous trees, will take longer to decay. Stir sawdust thoroughly into the pile or use very thin layers. Coarse wood chips will very slowly decay, and are probably better used as mulch unless you have lots of time to wait. Be sure not to compost chips or sawdust from any sort of chemically-treated wood -- you could be adding toxics like arsenic to your pile if you do.

• Wool rags

• Weeds and Other Garden Wastes

  Many types of weeds and old garden plants can be composted. Avoid weeds that have begun to go to seed, as seeds may survive all but the hottest compost piles. Some types of weeds are 'pernicious weeds' and will resprout in the compost pile -- avoid using these unless they are thoroughly dead. Green weeds are (you guessed it) a 'green', while dead brown weeds are a 'brown'.

• Urine

  That's right - Pee on your Pile

What Not to Compost - The OUT List

• Black walnut tree leaves or twigs

  Releases substances that might be harmful to plants

• Chemically-Treated Wood Products

  Sawdust is often available from constructions sites, friends, or your own building projects. If you are considering composting sawdust, be sure of the origin of the sawdust. Sawdust from chemically-treated wood products can be bad stuff to compost. For example, take pressure-treated wood (sometimes called CCA), which usually has a greenish tint to it (I have also seen it in other colors). It contains arsenic, a highly toxic element, as well as chromium and copper. There is evidence to suggest that arsenic is leached into the soil from these products when they are used to make compost bins or raised beds, so composting the sawdust would certainly be a mistake. You may wish to read the 'Letters' section of Organic Gardening, April 1994 and July/August 1992, for more information. Avoid other chemically-treated wood products and sawdust as well, such as wood treated with creosote or 'penta' preservative. Additionally, Chemically-Treated Wood is treated so as to make it less susceptable to rotting - something you want your pile to do.

• Coal or Comercial Charcoal Ash (like Kingsford)

  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. Egg shells are fine and add calcium to the soil

• Diseased or insect-ridden plants

  Many plant disease organisms are killed by consistent hot composting, but it's difficult to make sure that every speck of the diseased material gets fully composted. It's best not to compost diseased plant material at all, to avoid reinfecting next year's garden.

• Fats, grease, lard, or oils

  Create odor problems and attract pests such as rodents and flies

• Human Waste

  Human feces can contain disease organisms that will make people very sick. Composting human feces safely requires that the compost pile reach high (thermophilic) temperatures over a period of time. It isn't necessarily that difficult to reach these temperatures in a home compost pile, but the potential health costs of improper composting are high. Composting of human feces should not be attempted, except by experienced 'hot pile' composters who are well informed of the temperatures and times required to kill pathogens, and who are willing to take 100% responsibility for the process and product.

• Meat or Fish Bones Scraps and Fatty Wastes

  These materials are very attractive to pests (in an urban setting, this could mean rats...). In addition, fatty food wastes can be very slow to break down, because the fat can exclude the air that composting microbes need to do their work.

• Pernicious Weeds

  Morning glory/bindweed, sheep sorrel, ivy, several kinds of grasses, and some other plants can resprout from their roots and/or stems in the compost pile. Just when you thought you had them all chopped up, you'd actually helped them to multiply! Don't compost these weeds unless they are completely dead and dry (you may want to leave them in a sunny place for a couple of weeks before composting). Remember also that composting weeds that have gone to seed will create weeds in next year's garden, unless a very hot pile temperature can be maintained to kill the seeds.

  However, If you just throw these on the top for a day or so before turning them into the pile it should be OK since the heat of day and dry air will kill them good. Also, if you turn the pile often, any seeds that sprout and any weeds that try to take hold will never get a chance to establish themselve.

• Pet wastes (e.g., dog or cat feces, soiled cat litter)

  Might contain parasites, bacteria, germs, pathogens, and viruses harmful to humans. It is best NEVER to use them in compost piles. Some people do bury them 8" deep in the soil, but ONLY in areas where food crops are never grown.

• Yard trimmings treated with chemical pesticides

  Might kill beneficial composting organisms