Most Acers like a slightly acidic soil, ask at the garden store for acidic plant feeds for that type of plant, Rhododendrons as well as Azaleas and many other lovely plants that originate from that region all like the same type of acidic soil.
Hope this helps you out a bit.
Diana is absolutely correct and you should do soil tests, I do them every other year for instance on my veg beds as each year they do change their PH depending what type of veg I have planted / grown in the beds, Garden soil also changes over the years, I grow a lot of plants that require acidic soil, fortunately on the West Coast of Scotland, there is this type of soil in many, many areas and the soil is very sandy, to compensate this, I add loads of horse manures, leaf mould and as I have thick woodlands also, I have plenty ready made leaf litter that helps keep the acidic soil and the ph balanced for the Rhododendrons, Azaleas, Camellia's Acers etc.
Acers like free draining soil BUT that does not mean dry at the roots therefore you need to add humus to the soil, BUT a soil test will tell you just what is required to be added, you can buy a cheep soil testing kit from the garden centre, you don't need a big expensive and complicated testing kit., the cheap ones last ages and do loads of tests, make sure you test several areas of your cultivated garden areas as they can be huge differences within the same Garden.
Hope all the replies help you get things sorted out soon and you have a nice small shrub / tree, they are beautiful and when used as a specimen plant close to other plants with textured leaves and colours, they are quite spectacular.