Juniper 

scopulorum 'Skyrocket'

Probably the most narrow columnar Juniper the 'Skyrocket' has blue-green foliage.  RHS Award of Merit.

Bloom Time:  None.

Growth Habit:  Upright, 12-15' in height, may only be 2' wide at base.

Foliage:  Blue-green.

Sun/Shade:  Sun.

Hardiness Zones:  3-7.