I had been developing a coir based organic plant growth medium for a couple of years and was getting fairly good results. However I wanted to know exactly what the actual nutrient levels in the mix were so I had a sample tested by a professional soil testing lab. The test was fairly expensive but it provided a comprehensive set of results. What surprised me was a high ammonium content and practically no nitrate.
Naturally occurring and ubiquitous nitrifying bacteria convert ammonium to nitrite and then to nitrate. I came across a research paper from the late 1940s which described a nutrient medium for growing nitrifying bacteria. Many of the ingre….