my nutes list the following.
30% Nitrogen Total (N)
- 3.3% Nitrate nitrogen (NO3-N)
- 2.1% Ammoniacal nitrogen (NH4-N)
- 24.6% Urea nitrogen (Ur-N)
10% Phosphorus pentoxide (P2O5)
10% Potassium oxide (K2O)
0.12% Iron (Fe)
- 0.12% Water soluble
- 0.12% Chelated by DTPA
0.06% Manganese (Mn)
- 0.06% Water soluble
- 0.06% Chelated by EDTA
0.02% Boron (B)
0.015% Copper (Cu)
- 0.015% Water soluble
- 0.015% Chelated by EDTA
0.010% Molybdenum (Mo)
0.015% Zinc (Zn)
- 0.015% Water soluble
- 0.015% Chelated by EDTA
That's exactly the info I was looking for, did not find it after a Google search. Good food for a typical organically enriched potting soil. Not enough for a totally inert soil-less medium like you're using. You'll have the best results with a complete food like Dyna-Gro, which has ALL 16 essential elements.
Not sure why the 1/3 rate? Seems to me if you're not getting any nutrition from the medium that you'd want to provide more nutrition in the form of a plant food. What are you afraid of? You have to combine the nutritional value of what's being provided in your soil with what you're applying and go from there. Sum of the parts thingie....
Curious, what is the organic soil you're using and if you know, what nutritional value or charge does it have?
As an aside, it's not a zinc issue. Your food has zinc and like the pH drills, someone's guessing, not knowing.
Ben