" I have added coffee grounds to the soil to help get the alkaline soil they need."
1) blueberries need acid soil, which is the opposite of alkaline
2) coffee is acid, but most of the acidity is in the coffee. If you are talking about used coffee grounds, they have very little acidity left in them
tom is right that you need to get a pH meter, so you will know how acid (or not ) your soil is when you start and after you treat it and you need to add something to your soil that is specifically made to acidify it. Fertilizer that is labelled for blueberries or labelled for azaleas (which are also acid lovers) will have the right pH. Or you can add sulfur compounds. Once you get your soil acidified, using acidic mulch ingredients like oak leaves, pine straw or pine bark in a 3- to 4-inch-thick layer will help maintain it that way.