The Disadvantages of Spruce

Not Drought Tolerant

• Spruces thrive in moist, well-drained soils in moist, cool climates, and do not do well in areas prone to drought conditions. Norway and Colorado blue spruces are especially sensitive to summer drought, and if not given sufficient irrigation, they can suffer from branch or twig dieback, browning or yellowing needles and premature needle drop.

  During drought conditions, the Colorado State Extension website suggests watering trees about three times a month to about 12 inches deep, extending the irrigation 3 to 5 feet beyond the drip line all around the tree. Applying a 4-inch layer of organic mulch, such as shredded bark, leaves or wood chips, on the ground around the tree helps retain consistent soil moisture and prevent drought damage.

Large Size

• Although attractive ornamentals, spruce trees often get too large for their allotted growing spaces. Fast-growing Norway spruces reach up to 80 feet tall with 40-foot spreads, while the Colorado blue spruce typically matures to about 50 feet high with 25-foot spreads. Most spruces need to be planted in large, open locations that offer plenty of room for the roots and branches to spread. Having too small of a space for proper root development causes trees to suffer from symptoms similar to drought damage, even if your area receives plenty of rain. In addition, spruces growing in small areas often become crowded by other trees to the point that the branches can't stretch to receive appropriate amounts of sunlight. This shading can cause the lower limbs to die and the tree will lose its attractive, symmetrical shape.

Cold Sensitivity

• Although spruce trees become basically inactive during the cold winter months, they continue to lose a bit of moisture through their needles. When the foliage loses more water than the roots can replace, the needles start browning from the tips towards the bases, a condition known as "winter burn." If your area experiences a late spring frost or freeze, your spruce might also suffer cold damage and exhibit drooping, wilting or dying shoots. Mulching around your spruce can help conserve crucial soil moisture, as can wrapping burlap around trees exposed to the winter wind and sun.

Insect Infestations

• Spruce trees can suffer from various insect infestations, particularly from spider mites and adelgids. Spider mites are tiny, sucking pests that remove the sap from the needles, causing yellow specking, dry needles and twigs, needle drop and reduced vigor. The cooley spruce gall adelgid, another sap-sucking pest, can cause tip dieback, curled twigs, shoot and needle distortion, discoloration of foliage and odd-looking, brown cones shaped like pineapples.

  Spraying your tree with a dormant oil in late fall helps control spider mite populations and manage adelgids. Following the instructions on the product's label, mix about 7 1/2 tablespoons of dormant spray oil into 1 gallon of water. Spray your tree until the entire surface of the foliage looks wet for optimal pest control.