Ajusting potted blueberry pH with sulfuric acid and well water
Today in the space of 10 hrs we adjusted our blueberry media from a starting pH of 6.8 to 3.8 with sulfuric acid and back to 4.7 with alkaline well water. This is so easy I don't see the need for anything else to get off to a good start with potted blueberries.
Store bought battery acid is 33% sulfuric acid. I dilute it by pouring one qt into 9 qt water. This gives a stock solution that is 3.3% sulfuric and makes it much safer to handle.
It took about two qts of the stock solution mixed in a couple gallons of water leached thru ~12 gallons of potting mix to lower pH to 3.8. Had we been more careful we could have stopped at 4.5 to 5. But having gotten to 3.8 we leached with alkaline well water three times to get back to 4.7.
We'll wait a couple days to see if the pH is stable before using the mix.
We earlier adjusted from 6.8 to 4.4 after planting with excellent results. We used well water adjusted to ~ 3.5 pH to do that.