If the bottom branches are dead then remove them.  Blue Spruce often has fungal diseases. Closely inspect the tree for signs of diseases. http://www.extension.umn.edu/garden/diagnose/plant/evergreen/spruce/

http://www.extension.iastate.edu/harrison/news/common-diseases-blue-spruce

 Newly planted trees require routine watering. Typically, 5-7 gallons, applied to the root ball once a week, is an appropriate quantity of water to add to a newly planted tree.  Examine the soil moisture 4-8 inches deep to determine the need for water. If the soil feels dry or just slightly damp, watering is needed. Soil type and drainage must also be considered. Well-drained, sandy soil will need more water, and more often than a clay soil that may hold too much water. A slow trickle of the garden hose at the base of the plant for several hours or until the soil is thoroughly soaked is the best method. Short, frequent watering should be avoided, as this does not promote deep root growth but rather, the development of a shallow root system that is vulnerable to several environmental stresses. Adding 3-4” of mulch around the base of the plant will help the root system develop. By mulching plants, a more favorable environment is provided for the tree roots. Mulch allows better infiltration of water, holds soil moisture, limits weed growth, and discourages injury from lawnmowers and weed whips.  A 3-6 inch layer of mulch, spread to form a 3-6 foot diameter circle around the plant, should be applied. Keep the mulch material from direct contact with the tree trunk.

  http://www.extension.umn.edu/garden/yard-garden/trees-shrubs/fertilizing-evergreens-conifers/