Types

• Two spruce species in particular have dwarf cultivars for landscape use in gardens in the U.S. The dwarf Alberta spruce (Picea glauca "Conica") develops into a narrow triangular evergreen shrub, while the numerous dwarf selections of Norway spruce (P. abies) and blue spruce (P. pungens) tend to develop into plump, rounded or irregularly mounded shrubs after several decades of growth. Native to colder climates, all dwarf spruces prosper in regions with a cold to very cold winter and where summers don't get too hot, such as U.S. Department of Agriculture plant hardiness zones 3 through 7. Knowing what species or cultivar of spruce you have helps determine what problems may be afflicting the plant, causing brown foliage. Dwarf spruces slowly die off in regions with too mild winters and hot summers.
  
  

Soil Moisture

• Dwarf spruces that are stressed by overly wet, soggy soils and overly dry soils will develop brown, dying foliage and twigs. A deep, moist but well-drained garden soil promotes the best growth and longevity of all spruce trees. The correct soil moisture levels ensures roots grow in good health and provide the water and nutrients needed to sustain all foliage year round. When dwarf spruces are first planted into the landscape, they need irrigation to ensure the root ball does not dry out while the roots begin to grow out and establish into the surrounding topsoil.
  
  

Winter Issues

• Dwarf spruces retain most of their needles through the cold winter months. While the needles conserve moisture through thick, waxy cuticles, drying winds can cause some parts of the shrub to dehydrate and brown. By spring, these areas are fully dry and dead. Winter sun can contribute to needle browning on spruces. While air temperatures may be below freezing, direct sunlight -- especially in the afternoon -- can warm up the needles to above freezing. Then, after sundown, the liquid sap in the needles quickly refreeze, causing tissues to rupture and desiccation to occur. Shielding dwarf conifers from afternoon sun and direct bombardment by winter winds can diminish browning and dieback of needles.
  
  

Other Insight

• Most spruces do not grow well in alkaline soil. High pH soils limit the uptake of certain nutrients that can lead to stunted, yellow growth or brown needles as twigs die. If the soil becomes too hot and dry in the summer, drought stress can lead to needle browning. Irrigate as needed to ensure the dwarf spruce is not drying out all over, but do not create a soggy soil. Spider mites often create webbed nests in spruces when conditions are warm, windless and dry. These pests suck sap from the plant -- especially dwarf Alberta spruce -- that leads to needles drying out, browning and dying. Dislodge the mites with a strong stream of water or by saturating them with insecticidal soap or oil.