What is STA Certified & OMRI Listed Compost?

STA Certified 2.png

Available from

Kansas City Composting:

Black Gold Compost

STA Certified

STA stands for the U.S. Composting Council's Seal of Testing Assurance. It is designed to let the consumer know that the compost they are buying has been manufactured to strict standards, yielding a safe, consistent product.

In the early days of composting, everyone had their way of producing this wonderful soil amendment. Some used organic food scraps or landscaping waste, while others might add manure. Whatever the method, in the year 2000, it was decided that a standard should be adopted so homeowners and landscapers could rely on safe, consistent results year over year and the Seal of Testing Assurance was born.

While the industry helped design a testing program which included physical, chemical and biological tests, it was decided that outside independent labs would provide analysis. This way, users of compost could be assured that the compost they were buying would be scientifically analyzed, free of outside bias, so when it was STA Certified they knew they were getting the very best quality.

In addition, the program testing frequency was designed to correlate with the raw tonnage of compost produced by a manufacturer. At Kansas City Composting, as one of the Missouri's largest compost producers, we test monthly, the highest level of frequency the program requires.

So what does the laboratory test for you ask? In addition to rules which require us to be fully compliant with all Federal and State mandates to assure public health/safety and environmental protection, our compost is evaluated on the following properties:

  • pH

  • soluble salts

  • nutrient content (total N, P2O5, K2O, Ca, Mg)

  • moisture content

  • organic matter content

  • bioassay (maturity)

  • stability (respirometry)

  • particle size (report only)

  • pathogen (Fecal Coliform or Salmonella)

  • trace metals (Part 503 regulated metals)

What does STA Certified mean to you? All of our compost is tested at regular monthly intervals to make sure we offer the safest, most consistent compost on the market. In other words, when you see the U.S. Composting Council's Seal of Testing Assurance on your compost from us, you can be confident you're buying a safe and high quality product that will deliver consistent results in your yard or garden time and time again!

OMRI Listed Logo

OMRI Listed

OMRI refers to the Organic Materials Review Institute. OMRI is a non-profit organization that provides an independent review of a variety of products, from fertilizers to health care products, looking to certify those products that are to be utilized for organic production and processing, like our compost.

OMRI reviews products against a set of organic standards and once the product satisfies their criteria, the product is listed on their website under their Organic Products List.

OMRI's Mission (taken from their website):

OMRI's mission is to support the growth and trust of the global organic community through expert, independent and transparent verification of input materials, and through education and technical assistance.



Sign-up for our newsletter and receive special offers and seasonal gardening tips. Each of our newsletters feature articles on the very latest in recycling and organic technologies, as well as, useful links for the professional and hobbyist alike!