If you want it simple, here it is.
Go to HD or Lowes and get a 40lb bag of Dolomite lime, a whopping $4.50. Or, Calcitic lime, a bit more @~$15 for the 40lb bag. Just NOT hydrated lime.
Add 2tbl/gallon of mix, or 1cup/cf of mix. Scratch into the surface if a plant is there, but better added to the mix before use. Not sure what the 1/4tsp/2 gallons is supposed to do (from above). Not much, I'm sure. Give it a couple of weeks to get working well.
This is nothing but ground up limestone rock and is not going to burn or harm anything. It will correct your low pH though and supply Calcium and Mag to boot. I've grown things in crushed limestone. Drainage sucked, but nothing got burnt.
I haven't used my pH meter in well over 2 years and haven't pHed anything going in (water, nutes, teas, whatever), in close to 4 years. No need with a well limed soil.
You can do it the simple way by adding lime, or the hard way by pHing everything. Which still doesn't work as you've noticed. The soil will buffer whatever's added to the soils pH, but the pH of whatever's added has at best only a temporary effect of the soils pH.
Wet