Graph of Osmocote+ Time Release at High and Low Temperatures

I hope this is the correct place to post this. No idea if others will find it interesting or useful. I read a few times that Osmocote can be "shut down" by lowering temperatures a little. I was interested to see what the effect of temperature really is on this CRF.
I made up a solution of 2% Osmocote by weight (20 grams Osmocote in 1 litre, 1000 grams of distilled water). I tried to hold the solution at three different/constant temperatures. In practice, each temperature varied about 4F degrees (+- 2F).
I took readings every 12 hours for 7 days. The results are shown in the graph. My quick interpretation is, temperature lowers the rate of release, but even when temperature is low, the fertilizer releases at more than 2/3 the rate compared to when the temperature is high (mid-40's vs. mid-80's).
I was somewhat surprised to find the PH of the solution did not change with concentration, but did vary with temperature. The warmer the temperature, the lower PH:
44 F = 5.7 PH
68 F = 5.5 PH
83 F = 5.2 PH
This may well be due to the temperature compensation of my PH meter being inaccurate. Dunno...
Anyway, I hope this is might prove useful somehow when working with Osmocote. I mix the stuff with water, let it sit, adjust PH and PPM, then use it to water/feed.

PPM3.jpg
 
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