Compost refers to decomposed organic waste that is used as fertilizer. It can be considered a type of recycling and is used in of sustainable agriculture. Compost is one of nature's best mulches and garden amendments, improving soil structure, texture, and water-retention characteristics. The organic matter in compost feeds microorganisms which naturally produce nitrogen, potassium, and phosphorus. Producing and using compost also helps reduce human production of waste — landfills are brimming and nobody wants one in their backyard! Best of all, compost is cheap and the City of Davis will even provide you with a cheap compost bin.

How to compost

Almost any organic material is suitable for composting, but the pile needs a proper ratio of carbon-rich materials (aka "browns") and nitrogen-rich materials (aka "greens"). Brown materials include dried leaves, straw and wood chips while green materials are fresh vegetation such as grass clippings and kitchen scraps. Achieving the best blend of greens:browns is not an exact science, but a good target ratio is about 25:1 part browns:greens by weight. Too much carbon hinders breakdown of materials while excess nitrogen makes for a big stinky pile.

All additions to your compost pile will decompose more quickly if they are chopped up before adding. Grass clippings break down quickly and contain as much nitrogen as manure. Since fresh grass clippings will clump, become anaerobic and start to smell, mix them with plenty of brown material or dry them out in the sun before composting. Most kitchen scraps can be composted, but meat products, dairy products, and high-fat foods will decompose slowly, smell bad, and attract pests and vermin. Egg shells are great, but decompose slowly and should be crushed first. Be sure to bury food scraps deep in the pile—don't leave them on top or you'll just be feeding the rats.

Leaves and other large pieces of materials will break down slowly, so chipping wood and grinding leaves will reduce the size of your compost pile and speed decomposition. Also keep in mind that some leaves, such as live oak, magnolia and holly are too tough and leathery for composting while all parts of the black walnut tree contain a toxin that survives composting. Eucalyptus leaves can also contain a toxin that may be harmful to other plants after composting. And of course, avoid using poison oak and sumac!

Please read this article on the use of eucalyptus in composting. http://slosson.ucdavis.edu/documents/1993-19942140.pdf More on the benefits of Eucalyptus in composting for plants and vegetables… A California research project on Eucalyptus leaves in compost: http://ucanr.org/repository/CAO/landingpage.cfm?article=ca.v047n03p22&fulltext=yes. The finding that both sludge products similarly affect crop growth indicates Eucalyptus trimmings (present in the compost, but not in the heat-dried sludge) do not suppress crop growth at the rates being evaluated in this study. This is an important point because it was initially feared that allelopathic compounds in the Eucalyptus would inhibit crop growth. The authors hypothesize that the composting process degrades the allelopathic compounds into harmless products. In-ground composting is a very simple and pest-resistant way to compost your food scraps. Just bury them in the ground!

In summary, the field experiment showed that incorporating sewage sludge compost 4 inches deep as a soil amendment in spring plantings significantly increased yields of onion, snapdragon, turf and spinach. Greenhouse experiments produced similar results and demonstrated that the presence of Eucalyptus trimmings in compost does not depress yields.

Once you've got a good pile going, it will eventually decompose into a rich dark humus, but it may take a year if you do nothing else! To speed up the process and harvest your humus as early as four weeks, water your pile occasionally and turn it over about once a week. Organic waste needs water to decompose, so keep your pile about as moist as a wrung-out sponge. Don't go too nuts with the water though, a soggy compost pile becomes anaerobic, which will slow decomposition. If you're building your pile with wet materials mix in dry materials as you go along, and if your materials are particularly dry, wet it down as you build it up. Oxygenating your compost pile is the other part of this equation: the pile needs to be turned or mixed with some regularity because the temperature in the middle of the pile is warmer than the outer areas and you want to get the whole thing to cook evenly. Whenever you turn your compost pile, check it for moisture and add water as necessary.

The City of Davis has a lot of composting information on their website, with pages on backyard composting, worm composting and composting food scraps. Videos, fliers, pictures and more.

A very simple way to compost your food scraps is just to bury them at least 8 inches deep in your garden, a process known as in-ground composting. Garden soil provides a natural barrier that keeps out flies and other pests, and holds in moisture and odors. If you have dogs that like to dig in your garden, this might not work very well.

Food scraps can be buried in empty areas of vegetable and flower gardens, or in holes outside the drip line (below the ends of branches) of trees and shrubs. This is great in the fall and winter to prepare your veggie beds for spring planting. Dig a hole or trench about 1 foot deep. Add 2 to 3 inches of food scraps to the hole. Chop and mix scraps into soil, then cover the food scraps with at least 8 inches of soil to keep pests out.

Food scraps may take from 1 to 6 months to decompose depending on the season, moisture, soil and the type of food scraps that are buried. Seeds and small seedlings may be planted on top of buried food scraps immediately. Large transplants should not be planted until the food has decomposed. Do not bury more food scraps in the same place until the first scraps have been fully composted.

Compost Classes

  • The City of Davis offers free composting classes in the fall and spring. In addition to backyard composting, these classes place a particular emphasis on simple, pest-free methods of composting food scraps. After attending a class, Davis residents can sign up to receive a starter set of composting worms for $5 and residents in single-family homes can receive a backyard compost bin for $10. To register for a class, call the Public Works at 757-5686, email pwweb@cityofdavis.org or RSVP to the Facebook event.

Fall 2012 classes:

Class attendees that live in Davis can enter to win a free worm composting starter kit, including a worm bin, composting worms and bedding—all set up and ready to compost your food scraps.

      • Wednesday October 17 from 6:30 p.m. to 7:30 p.m. in the Veterans’ Memorial Center Game Room
      • Friday, October 19 from 3:00 p.m. – 4:30 p.m. in the Veterans’ Memorial Center Club Room
  • The City of Davis offers a year-round compost correspondence course to Davis residents in single-family homes. To enroll, call Public Works at 757-5686, or email pwweb@cityofdavis.org. Once you receive the packet, read the materials inside, fill out the enclosed quiz and return the quiz to the Public Works Department. A city staff-person will contact you to let you know that your quiz was received and that your compost bin is available for pick-up. A $10 fee will be charged for a compost bin.
  • Project compost will often offer classes on composting and worm composting.

Composters

Local Compost Experts

Compost Users

Composting Groups

Users of compostable plates and utensils

Events

Restaurants

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2006-06-04 22:02:33   According to DavisRecycling.org, you can call 757-5686 to get a free compost bin! —CharlesWinkelmann


2007-01-22 03:05:24   Or you can take out a spade and make one yourself! Assuming you have property you can dig on. Like my dad does, we had rotating compost holes in the backyard at all times when I was growing up (and the practice lives on to this day) —StevenDaubert


2008-06-07 02:41:25   Anyone know where I can get a 55-gallon drum that was used for something edible? —PeterGee


2010-05-23 09:13:58   Please read this article on the use of eucalyptus in composting. If you are going to present facts, they should be backed by research: http://slosson.ucdavis.edu/documents/1993-19942140.pdf

More on the benefits of Eucalyptus in composting for plants and vegetables… A California research project on Eucalyptus leaves in compost:

http://ucanr.org/repository/CAO/landingpage.cfm?article=ca.v047n03p22&fulltext=yes The finding that both sludge products similarly affect crop growth indicates Eucalyptus trimmings (present in the compost, but not in the heat-dried sludge) do not suppress crop growth at the rates being evaluated in this study. This is an important point because it was initially feared that allelopathic compounds in the Eucalyptus would inhibit crop growth. The authors hypothesize that the composting process degrades the allelopathic compounds into harmless products. In summary, the field experiment showed that incorporating sewage sludge compost 4 inches deep as a soil amendment in spring plantings significantly increased yields of onion, snapdragon, turf and spinach. Greenhouse experiments produced similar results and demonstrated that the presence of Eucalyptus trimmings in compost does not depress yields —webscience