FAQ's
What is Compost and why should I use it?
What is Compost?
Why should I buy and use compost?
Is compost safe?
How is your product organic?
Aminopyralid
What are the effects of you accepting meat in your waste stream? Cedar Grove Position on Meat Scraps.
Benificial Microbes, are they still in your compost?
How can Cedar Grove be sure there are no metals coming in?
How much compost should I use?
Is it ok to Garden in 100% Compost?
Do I need to add fertilizer to my garden?
How does compost affect the Ph?
Why are there mushrooms or sometimes ash colored webs?
Why is there an ash colored layer?
Why is there sometimes weeds in delivered loads?
Cedar Grove Compost Quarterly results: Fine Grade Compost
What do these results mean?
What is compost?
Compost is the product of natural decomposition of plant and animal wastes by bacteria, fungi, worms and other beneficial organisms. Cedar Grove Compost is made from locally recycled yard trimmings, food scraps and clean wood waste from residential curbside and commercial collection programs across the Puget Sound region.
Why should I buy and use compost?
Buying and using Cedar Grove Compost completes a local recycling loop and supports a sustainable local economy.
- Compost is a concentrated source of plant nutrients, stores water for plants and feeds soil life that help plants get nutrients from the soil and fight off pests.
- Compost helps build and maintain healthy soils while minimizing erosion, chemical and water usage.
- Adding compost to your soil is more important and beneficial for most plants than using fertilizer.
- Composting these materials diverts them from costly transport to distant landfills, where they would generate methane—which is a "greenhouse gas" that is 21 times more potent than carbon dioxide in creating climate warming.
Is compost safe?
Cedar Grove Compost is made from clean yard trimmings, food scraps and wood that are separated at their sources before being mixed with trash. Non-organic material that is accidentally mixed in with these clean compostables is removed by hand-sorting and screening prior to composting, and screening of finished compost.
Cedar Grove uses a state-of-the art, computer-controlled system that ensures the compost heats to temperatures hot enough to kill diseases and pests, and biodegrades any toxic chemicals that may be present.
Cedar Grove takes organic material that would otherwise be mixed in with trash and shipped to landfills at great expense, and processes it through a state of the art composting system to produce a clean soil amendment. Compost supports healthy plant growth and prevents the need for use of synthetic fertilizers and pesticides that can pollute our water and endanger our health. Compost is used to prevent soil erosion, reduce and clean storm water discharged into local streams and lakes, and to replant disturbed and polluted sites.
Aminopyralid
I understand that commercially produced compost has the herbicide aminopyralid that can inhibit plant growth. Should I be concerned about this with Cedar Grove's compost?
Aminopyralid is found in livestock manures and animal bedding. Because Cedar Grove does not accept manure or any of these types of feedstocks, it is not an issue in our compost. In addition, we perform growth trials and biossays on our sale batches.
If my neighbors use pesticides in their garden and put treated plants in the curbside collection bin, how can your product be registered organic?
Years of testing by certified laboratories have shown that pesticides are undetectable in in the finished Cedar Grove Compost. The naturally occurring microbes and heat generated during composting break down most toxic chemicals into safe compounds. In addition, the large volume of clean yard trimmings, food scraps and wood processed at Cedar Grove dilutes contaminants to safe levels that are well below regulatory standards set by the USEPA, Washington Department of Ecology and local Public Health Districts.
Materials certified for use in organic agriculture do not have to come from organic sources. Barnyard manures and byproducts like bone or feather meal, and plant based fertilizers such as cottonseed meal that are approved for use in producing organic crops are not required to originate from animals or crops that are raised organically. They may contain residues of chemicals and even heavy metals used as fungicides.
With meat included in organic waste recycling programs, do steroids, pathogen like e-coli, and hormones show up in finished compost. What about the prions from Bovine Spongiform Encephaly (mad cow disease)?
The naturally occurring microbes that make compost also break down steroids and hormones into simple, safe compounds; and the heat generated in the process kills pathogens like e-coli, salmonella. Cedar Grove Composting monitors the piles to make sure that temperatures are maintained at 150 F for at least 3 weeks in the composting process—well beyond regulatory requirements, and the finished compost is tested in accordance with state laws to demonstrate that disease causing pathogens are not present.
Prions suspected for causing BSE do not break down in composting or other heat treatments. However, BSE is spread by ingestion of infected animal tissue (brain, spinal cord and related nervous system parts), not by meat or casual contact with infected animals or their wastes. BSE is not considered a health risk in the US food-chain due to extensive food supply controls. To learn more, please visit:
http://www.mad-cow-facts.com/about-mad-cow/
Your compost system gets very hot, which is great for killing off weed seeds and pathogens. Does it kill off the beneficial microbes, too?
The organic matter in finished compost is a high quality source of food for diverse organisms that repopulate it during the curing phase at our facilities, and from natural sources in and around your garden. The positive conditions created by adding compost (balanced nutrients, neutral pH, moist and well aerated soil) favor diverse populations of soil organisms. In these conditions beneficials will generally keep pests under control. At the end of the process, the compost is extremely active with microbes.
I am concerned about fish going into the compost bin since it is known to have mercury. How can Cedar Grove be sure there are no metals coming in?
Cedar Grove tests all batches of compost for 14 metals prior to sale, to ensure compliance with Washington State regulations (for 9 metals plus other contaminants) and voluntary compliance with the US Composting Council Seal of Testing assurance program. Cedar Grove Compost is consistently well below the safe limits for metals set by Washington Department of Ecology and the USEPA. The USEPA standards are set to protect children who eat soil, and WDOE’s standards are even more restrictive.
A recent review of test results from the past four years showed that Mercury has not been detected at any level in Cedar Grove Compost during that period.
How much compost should i use? Can i use too much? Do i need to add fertilizer too?
How much compost shout I use in my garden?
Recommended compost application rates for various plantings are listed below. The higher rates are for sandy soils, lower rates for heavy clay:
Lawns: 1 to 2 inches of compost mixed 8 inches deep into soil.
New Shrub and Tree beds: 2 to 4 inches of compost mixed 8 to 12 inches deep.
Established Shrub and Tree beds: Mulch with 2-3 inches of compost/bark mix every few years.
New Annual Gardens: 2 to 4 inches of compost mixed 8 to 10 inches deep.
Established Annual Gardens: 1 to 2 inches each year, mixed a 2 to 6 inches deep.
Is it OK to garden in 100% compost? Is it possible to use too much?
Most plants will grow vigorously in 100% compost, but it is best to mix compost with mineral soils (clay, sand or loam) for gardening, to have ideal texture and provide anchorage for plant roots. 100% compost does not drain well, and may encourage pest or disease problems. Lawns grown in too much compost will be soggy and uneven.
Do I need to add fertilizer to my garden if I use compost?
It depends on what you are growing and how much compost you use. Mature compost like Cedar Grove produces should provide all the nutrients needed for shrubs and trees when applied at the application rates recommended above. Compost releases nutrients slowly, especially in cool weather, so it is not a complete substitute for fertilizers on fast growing annual crops or lawns—it may allow reduction of recommended fertilization rates by 50% on these plants.
How does compost effect the acidity (pH) of soils?
Finished yard trimmings composts are close to neutral in pH (7.0) , and help to buffer our naturally acid soils.
Why are there sometimes mushrooms or grey ash-colored webs on compost? Are they safe?
Mushrooms were growing on a pile of compost that sat in our yard this winter? Why? Are they poisonous?
Mushrooms are natural decomposers that thrive on partially decomposed wood chips and bark. These materials persist in the compost for years. They help keep the soil loose and serve as food for beneficial soil life –like mushrooms—which eventually break down and release the nutrients to plants. These are "wild" mushrooms. They are not likely poisonous, but it is recommended that curious children and pets be kept away from them. Turning or mixing a pile will usually stop mushroom growth.
Why is there an ash-colored layer in the pile of compost delivered a few days ago? Is it burnt?
Actinomycetes (ac-tin-o-my-seet-ays) are a natural bacteria that form long gray fungi-like threads, resembling spider webs or ash, that stretch through compost. These bacteria are primary composters of tough plant materials like bark and woody stems. They are present at every stage of the composting process, and are most numerous on the persistent woody materials left in mature compost. They produce natural anti-biotics that help fight plant diseases. Once the compost is spread and mixed into the soil, the actinomycetes will no longer be visible because they cannot develop dense colonies in the soil
Actinomycetes need water, oxygen, and food to be active. When compost is picked up from Cedar Grove for delivery, material from the middle of the pile is aerated and microbial life is stimulated. If you dig into the pile a few days after delivery, you will see a gray layer beneath the surface and some steam. This is the actinomycetes hard at work, using the fresh air and to continue decomposing resilient woody materials. This activity is normal and to be expected of any microbe-rich environment such as compost.
If compost gets so hot during decomposition, why are there sometimes weeds in delivered loads?
During the primary composting process at Cedar Grove, the material heats up to over 150 degrees F for at least two weeks. which is sufficient to kill all weed seeds. The piles are mixed twice, so that every part of the pile is exposed to at least a week of high temperatures. The product is then screened and left to cure for 2-5 months.
During curing, the pile is exposed to weed seeds blown into the property. Before product is sold the outside layer is scraped off and put back through the composting system, but additional seeds may be blown into the compost while it awaits sale or at resale yards at nurseries or soil vendors.