Question / Concentrate Solutions and ppm
 

Okay, I'm a little mathematically challenged and I have a question about the concentrate solutions and ppm.

I took my 20-20-20 powder mix and created the concentrate solution using the First Ray's direction of 3 pints hot water per 1 lb of net weight fertilizer.

Here is where I get confused. How do I measure for mixing up my fertilizer solution?

Is there a ppm measurement?

Quote from Ray's
"You now have a 25% concentrated solution of your original formula. In other words, if the original powder was a 20-20-20, your solution is one-fourth of that, or 5-5-5."


:scratchhead: I know I'm missing a step in here somewhere.

Go back to Ray's website and look at the fertilizer PPM calculator. Plug in your fertilizer solution N value (5) and your target PPM and click calculate. It'll tell you how many teaspoons of fert per gal of water.

Fertilizer PPM Calculator

There is also an easy conversion you can use:

If you divide 10 by the %N in your concentrate (or on the label, if working with that instead of the diluted solution), the result is the teaspoons needed per gallon of final solution for 125 ppm N.

So basically, you'd need 1/2 teaspoon of your original 20-20-20, or 2 teaspoons of your 5-5-5 dilution for 125 ppm N.

Is 125 ppm N a good general fertilizer concentration for orchids ? Or is there a source for recommended concentrations ?

Charlie