Do some of the ingredients in Pro-Gro contain iron which would cause a lawn to green up well?
There is inherently a lot of trace elements (iron being one of them) in the raw materials we use to create our natural fertilizers. It would be difficult, however, to quantify or qualify the iron content. Greensand, for example, is an iron-potassium silicate but much of the iron is bound in a tight mineral formation which, under sterile conditions would never be released. But since we provide food for soil organisms in our fertilizer blends, the resulting microbial activity not only releases the iron that is in our raw ingredients but also some of the huge warehouse of iron that is already in the soil. In an average acre of topsoil (~6 in. deep), there is ~100,000# of iron that can only be made available as an indirect result of biological activity.
