TKO to fight Diseases and add Potassium

I did a foliar application of TKO this evening.  TKO is a good fungicide because the phosphites in it and I hope to help control the powdery mildew that is showing up on the 1985 Miller plant with it.  TKO is also a good source of potassium and since a good portion of a pumpkin is potassium, I hope to keep the fruit growing with that. 

Although TKO is listed as 0-29-26 I don't believe the phosphites in TKO actually apply much available phosphorous to the plant.  From what I have read in the past, although phosphites are more mobile in the plants, a plant prefers phosphates to phosphites so the uptake is less.  It may be that pumpkin leaves can absorb it and convert it to phosphates when applied as a foliar application, but I haven't read anything that it is necessarily true for Atlantic Giant pumpkin plants.