My landscaper recommended Orgro as a soil amendment for an upcoming project...
My landscaper recommended Orgro as a soil amendment for an upcoming project not involving edibles. I usually use Leaf-gro as a soil amendment. When I asked him why he specified Orgro, he said it was to bring down the alkalinity in my soil (7.3 when i had it tested). I was unfamiliar with Orgro, but learned that it was "produced through the careful composting of treated waste water residuals (commonly known as biosolids) from the Back River Waste Water Treatment Plant in Baltimore." I posted a query on the Montgomery County MG listserve and did not receive positive response - although no one seemed to have actual experience with it. What can you tell me? Thanks very much.
We do not have our own research on Orgro. We can say the pH varies in composted products such as Leaf-Gro or Orgro. Our own publication on our website, lists Leaf-Gro as 6.8-7.2: http://extension.umd.edu/sites/default/files/_images/programs/hgic/Publications/HG42_Soil_Amendments...
The following soil test we found online shows Orgro as 7.2, but that is only one sample from one day:
The nitrogen level is very low, which can be helpful these days because of the new Maryland Fertilizer Law.