When I use liquid I water the pots. Then I fertilize with concentrated fertilizer. And I post-water lighty.
You mentioned once lemon juice or something like that for acid loving plants. Would that be the same?
The water here is pretty low pH but the azaleas seem to do OK. I water with a sprinkler on the hose, but I could probably. be creative with a bucket or something to add lemon juice or something similar. The azaleas get their own special acid loving fertilizer, but that means acid loving fertilizer yesterday, hose water for a couple of days, rain water next week, and then acid loving fertilizer. I wonder how the pH swing there affects the azaleas.