A few years ago I learned by accident if I put 6" of peat moss on my soil then till it in and plant peppers they grow very fast and get 5 tall. Peppers grow very large too. I figured the loose soil made it easier for the roots to grow better. Peat moss is known to make the soil acid so last week I decided to do an experiment.
I planted bell peppers and banana peppers a month ago they have grown only 2" taller in a month. A week ago I sprinkled acid stuff around the pepper plants to make the soil more acid like peat moss does and in only 1 week the plants are 6" taller.
I did not measure anything. Not knowing how much to use I sprinkled this stuff around all the pepper plants. I was worried too much might kill the plants so I gave some plants more than others. The plants that got the most grew the tallest. I have very good fertile soil for all the plants every thing in the garden had been growing very well except for peppers. It seems strange to me all of a sudden pepper plants grow 6" in one week. It has not rained in about 2 weeks. Acidifier is 12% sulfur with gypsum. I watered the plants to make sure the stuff went into the soil right then.
Online report from Tennessee State University shows Gypsum improves garden plant growth from 3 to 7 times for all plants. In the post I used gypsum in place of lime for BER after eating vegetables it leaves a very fine sandy gritty feeling on your teeth. It also gives vegetables a slightly different flavor so I do not use gypsum anymore. I hope it was not gypsum that made my peppers grow faster. I bought this acidifier many years ago and never used it, today I think I will throw it all in the weeds.