Topsoil is a poor choice as an ingredient for container soils. Maintaining a steady pH, or adjusting to a target pH is often a problem for greenhouse/nursery operations, and extremely difficult for hobby growers. I would advise you to skip the frustration and not even try to hit/maintain a target, choosing instead to learn how to help insure that media pH is estimated to be under 6.0 and use an acidifying fertilizer . Coir generally has a much higher pH than peat, so is probably not the best choice in a soil used for blueberries. You won't need to worry about bringing the plants indoors or offering any special cold protection in zone 9, either.

Do a search of this forum using the words blueberries soil pH and you'll find enough good information to keep you occupied well into the night.

Al

Yeah I've found a bunch of stuff but there is always something I can't find. The stores are all stocked with Christmas stuff lol. I've been able to get decent readings off my hydroponic equipment. I took my $10 lowes ph meter and it almost always gives me a ph of 8. Then I used the $150 meter on my lime tree and it read 5.13! Whats something you would recommend without soil additives or fertilizers until spring?

I found a mix that worked. Sitting at about 4.6-4.7. It took me a few hours playing with different combinations. Just kept adding peat moss until it hit my target range. BTW I did find perlite tucked in behind the Christmas trees.

... all the best to you.

Al

Ended up with one of the ones I saw that was a pine bark, peat moss and perlite mixture. Going with the pots actually allowed me to put them in the "utilities easement" which has better sun, they don't want anything in the ground. The trees are about 3 year old Tifblue.

just digged up this old thread, anyone can tell me the difference between peat moss and perlite?? I noticed these 2 ingredients are usually the mixture of soil for blueberries....