bottom line ..."Read Instructions" on the label
but in most cases the clue is in the word 'soap'
being a neem (azidectin) based product always dilute or things will get messy indeed
ph is really a soil thing, being soil its alive and looks to operate its own Ph
applying oil or spray to the leaf and stems, ph is really tolerant, so go ahead
you have bought a commercial preparation that at best is ok, for great
go for the cold pressed neem oil, just today I put some in my cats ears
the little fucker is as happy as ..
good luck
ps neem oil like weed is very addictive, try in in your curries ..no shit!