Citrus are pretty broadly tolerant of pH and soil chemistry in general. I would not worry about it so long as I were using a general purpose potting soil. It would probably be fine even with a special acid soil mix such as for azaleas but why would one bother. Rough lemon rootstock, though, may not like alkaline conditions (it doesn't like limestone soils) but few potting soils would be very alkaline.

Thanx gonebananas for the info,guess that explains why I couldnt find any specifics on Ph for them ;-)

Hi malcolm manners
Well since you gave me some numbers to go by i used my Ph meter to get a reading.
Im not happy...My tree is still in the 3 gallon pot I bought it in and it gave me a reading of 4.5 Ph.
You would think the people who grew them out would at least have the soil at the right Ph.
Its not like I need any help screwing my tree up LOL
It would have been nice to at least get a good start.
I have had it now for about 2 weeks and it hasnt really put on any new growth at all,guess I now know why.

Do you think when I repot into a 5 gallon it will balance its self out?
Do you have any suggestions to get it back on track?

There is a belief among many hobbyist citrus growers, and even some nurseries, that citrus like a strongly acidic soil, such as your 4.5 or even lower, but it's not true. Yes, I'd try to raise that a bit. Maybe a couple tablespoons of dolomitic or calcic limestone, worked into the top inch of soil, or if you are repotting into a 5-gallon pot, use twice that much, again, working it into the soil. It won't have much effect if you just put it on the surface.

I recently purchased a property with an amazing, productive Meyer Lemon Tree. The tree has been neglected for years and, although I typically wouldn't fix what's not broken, I feel I should fertilize it to remedy the neglect. I picked up some organic fermented grape skins and was wondering if someone could tell me if a light layer (less than 1") over the ground within the drip line of the tree, keeping clear of the trunk, could help or hinder the tree? Thank you.

http://citrusindustry.net/2019/04/23/soil-and-water-ph-play-a-key-part-in-nutrition/

About every three months I add a teaspoon of lemon juice to a liter (quart) of water and then water our indoor tree. In two weeks it usually blossoms and then little lemons follow. This way we have lemons year round. Don’t forget to pollinate those flowers with a soft artist paintbrush so the little lemons stay on the branch and mature.