Soil acidity or alkalinity, referred to as its pH, is a major consideration for most landscape plants, but it is not as important for blue spruce as it is for many other trees. The ideal pH for blue spruce is between 6.0 and 7.5, but this tree can tolerate soil ranging from highly acidic to highly alkaline.  If you are not sure of the soil PH around the spruce tree then it might be wise to limit the application of the lime to areas outside the drip line of the tree to limit any increase in the alkalinity of the soil which could prevent the uptake of essential minerals to the root system.  Thank you,