First, I would not necessarily trust the pH meter. Unless it is an expensive, laboratory grade model - not the kind you pick up at the garden center - it is unlikely to be very accurate. You would get a better assessment with the test strips and a bottle of distilled water. Or tell us what other plants you are growing successfully.

If you find you do need to lower pH, then agricultural sulfur is the recommended amendment to achieve this. But it takes time for the sulfur to do the job so it is typically added in fall for spring planting. If adding now (or after confirming the pH) just be aware that it will take some time to be effective. You may not see much of a response this growing season.

In addition to soil sulfur, cottonseed meal can also lower pH. Using coffee grounds is a myth. They add nitrogen but are near neutral pH.

I have read that pine needles will lower ph and putting a couple tablespoons of vinegar in a gallon of water and dispersing that over the area will lower the ph. A guy that runs one of those pot growing supply places nearby said to squeeze a lemon over the ground. I have read that some sulfates(sp) can be used are effective but leave heave metals in the ground.

I've heard and read a lot and that why I've come here.

All I have in this area is raspberries and hey just really drag their feet.

I also have blueberries in half wine barrels and I fertilize them with something that's for plants that need lower ph. They do pretty well but the fruit could be bigger.

You would need to use a LOT of cottonseed meal to lower the pH two full points!!

Much like the coffee grounds, pine needles will have no affect on pH either. That is a gardening myth! Adding vinegar to water may help to acidify irrigation water but it is not going to change soil pH. Nor is squeezing a lemon over it!!

All of this is pretty easily verified online. But you have to consider the source of your information. Stay away from pot growing websites and social media and YouTube. Instead focus on science based or .edu websites.

And finally, there is a limit on how much of a change you can make to an existing soil pH and for how long. If it is more than about half a point (like from 7.0 to 6.5), you are probably better off growing that plant in a container where you can tailor the soil specifically according to the plant needs.

btw, it is much easier to raise soil pH than it is to lower it...........