My neighbor picked up some compost from the city and went to the added measure of talking with someone in the city and asking for a copy of the tests that the city had run on the compost via a 3rd party independent lab.
In my previous post about herbicides in compost, I’d indicated that compost from the city of Berkeley is processed with organic waste from other cities with curbside pickup & is done in a central facility in Modesto, CA. The results of the test show some interesting things, such as a really high pH level of 7.97 (most plants need the pH to be around 6 or 6.5).
One interesting point was that the lab tested the compost by a tried and true method — seed germination. In that test, 100% of the seeds germinated in the compost indicated that at least for now, compost that is given away free in Berkeley is not contaminated with herbicides.
The question that I can’t easily answer is about the trace metals such as arsenic, lead, etc., and if the EPA limits are low enough. I’m not a scientist, but I do know that many EPA limits have been lowered repeatedly over the years as new information has surfaced. I may be overly cautious, but I’m definitely still leaning towards making and using my own compost since this test is 1 snapshot in time and the composition of the city compost can and will change depending on what people put into their curbside green bins.
Click here ==> Berkeley compost report <== to read the details of the Berkeley Compost Soil Test report
