My blueberry bushes love pinestraw for mulch. Or just pine mulch. YMMV. I do know they love acid soil. I’m sure the local garden center/coop has something for your soil?
I have been adding a little vinegar occassionally with the water.
The area they are in gets lots of rain run off and is very well drained. I think my problem with their health is the heat. The leaves have brown patches on the tips at times. They have not grown that much but otherwise seem OK.
There were a few blueberries already set on the O’Neil’s but the birds got those before I could pick them. They have been doing the same to my strawberries. I fixed that with netting.