Originally Posted by jidoka
Lol...and don’t think about the weight thing
How would you recommend choosing my inputs then?
let's take another one: I badly need phosphorus for example.
How would you'd say I choose how many triple super phosphate I should add?
I'm open to sending other samples in, but I don't want to use only trail and error. There are plenty of people who did trail and error before me, so no need to re-invent the wheel I would think.
With my calculations I would end up with 12g for 5gal of potting soil.
This is the reasoning:
- I want to add 1160 ppm of P to get closer to K.
- 19.3% of the weight of TSP is P so I need 1160/0.19 = 6000ppm of TSP.
- 5 gal potting soil, oven dried + sieved equals 2000g.
- 2000 * 0.006 = 12g of TSP for 5gal of potting soil.
I'll use more gypsum indeed. I need to push out the K, Mg and Na first. I will try to do this with acidified low ppm rain water + gypsum + a little P.
Thanks for sharing your take